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At least 1,315 records · Page 73Linked to original sources
PubMed2005

Critical involvement of hydrogen peroxide in exercise-induced up-regulation of endothelial NO synthase.

OBJECTIVE: Recent studies from our groups have indicated that endothelial nitric oxide synthase (eNOS) expression is increased in cell culture by both shear stress and by hydrogen peroxide (H(2)O(2)). In vivo, exercise training, known to increase both endothelial shear stress and oxidative stress, also increases eNOS expression. It is unclear if H(2)O(2) contributes to an increase in eNOS expression in response to exercise training. METHODS: To address this question, we generated mice overexpressing human catalase (hCat) driven by the murine Tie-2 promoter to specifically target this transgene to the endothelium (cat(++)). RESULTS: Vessels of cat(++) expressed significantly higher levels of catalase mRNA and catalase protein and activity but normal levels of eNOS. Exercise alone had no effect on catalase expression in C57BL/6. Wild-type littermates of cat(++) showed an increase in eNOS expression with 3 weeks of exercise (2.53+/-0.42-fold) comparable to C57BL/6 (2.93+/-0.45-fold). In striking contrast, 3 weeks of exercise had no effect on aortic (1.33+/-0.32-fold) and myocardial (1.1+/-0.2-fold) eNOS expression in catalase transgenic mice. CONCLUSIONS: These data suggest that endogenous H(2)O(2) plays a key role in the endothelial adaptation to exercise training by stimulating an up-regulation of eNOS.

Amitrole↗
PubMed2004

Grafts of immortalized chromaffin cells bio-engineered to improve met-enkephalin release also reduce formalin-evoked c-fos expression in rat spinal cord.

Transplantation of adrenal medullary tissue for terminal cancer pain has been tested clinically, but this approach is not practical for routine use because of the shortage of organ donors and lack of tissue homogeneity. As a first alternative step, we have generated immortalized chromaffin cells over-expressing opioid peptides, namely met-enkephalin. Rat chromaffin cells have been genetically modified with vectors containing expression cassettes with either synthetic met-enkephalin or pro-enkephalin gene coding regions, fused with the nerve growth factor signal peptide for secretion. After stable transfection and differentiation in vitro, met-enkephalin and pro-enkephalin cells had higher met-enkephalin immunoreactivity and secreted met-enkephalin levels, compared to control cells containing the expression vector only. In the formalin hindpaw-injection model, 15 days after subarachnoid transplant of cells, grafts of met-enkephalin and pro-enkephalin cells significantly reduced the number of formalin-evoked c-fos immunoreactive spinal neurons in the spinal cord, compared to grafts of vector-alone chromaffin cells. The use of such expandable cell lines, for chronic spinal delivery of opiates, could offer an attractive and safe alternative strategy based on ex vivo gene therapy for the control of opioid-sensitive chronic pain.

Analysis of Variance↗
PubMed1999

Designing biomaterials to direct biological responses.

We have set forth a design strategy for creating biomimetic materials that direct the formation of tissue surrounding implants or regeneration within porous scaffolds. Our studies have established that heterogeneous mimetic peptide surfaces (MPS) containing both the -RGD- (cell-binding) and-FHRRIKA- (putative heparin-binding) peptides, unique to BSP, in the ratio of 75:25 (MPS II) or 50:50 (MPS III) proved to be more biologically relevant and specific for RCO cell function. The initial response of human osteoblast-like cells to these surfaces was mediated by the collagen (alpha 2 beta 1) and vitronectin receptors (alpha v beta 3), whereas the vitronectin receptor alone dominated longer-term events (> 30 min). MPS II and III surfaces enhanced cell spreading and long-term events such as mineralization of the extracellular matrix compared to homogenous peptide surfaces and controls. Furthermore, extensive mineralization of the ECM deposited by RCOs occurred when the peptide was coupled to an interfacial interpenetrating polymer network (IPN) that resisted protein deposition (i.e., non-specific adsorption) and fouling. Work on thermo-reversible P(NIPAAm-co-AAc) hydrogels demonstrated the ability to create materials that can be delivered to the body in a minimally invasive manner and support tissue regeneration. These hydrogels can be modified to incorporate biofunctional components such as the biomimetic peptides, theoretically enhancing their ability to foster tissue regeneration. These results suggest that biomaterials can be engineered to mimic ECM components of bone (e.g., various organs) by grafting peptides in the appropriate ratios of the cell and heparin-binding domains, and ultimately modulate the expression of the osteoblast cell phenotype. Approaches similar to the one presented in this work can be used to design materials for hybrid artificial organs and other tissues.

Amino Acid Sequence↗
PubMed2006

E Proteins and Id2 converge on p57Kip2 to regulate cell cycle in neural cells.

A precise balance between proliferation and differentiation must be maintained during neural development to obtain the correct proportion of differentiated cell types in the adult nervous system. The basic helix-loop-helix (bHLH) transcription factors known as E proteins and their natural inhibitors, the Id proteins, control the timing of differentiation and terminal exit from the cell cycle. Here we show that progression into S phase of human neuroblastoma cells is prevented by E proteins and promoted by Id2. Cyclin-dependent kinase inhibitors (CKI) have been identified as key effectors of cell cycle arrest in differentiating cells. However, p57Kip2 is the only CKI that is absolutely required for normal development. Through the use of global gene expression analysis in neuroblastoma cells engineered to acutely express the E protein E47 and Id2, we find that p57Kip2 is a target of E47. Consistent with the role of Id proteins, Id2 prevents activation of p57Kip2 expression, and the retinoblastoma tumor suppressor protein, a known Id2 inhibitor, counters this activity. The strong E47-mediated inhibition of entry into S phase is entirely reversed in cells in which expression of p57Kip2 is silenced by RNA interference. During brain development, expression of p57Kip2 is opposite that of Id2. Our findings identify p57Kip2 as a functionally relevant target recruited by bHLH transcription factors to induce cell cycle arrest in developing neuroblasts and suggest that deregulated expression of Id proteins may be an epigenetic mechanism to silence expression of this CKI in neural tumors.

Adenoviridae↗
PubMed1993

Mechanism of HIV-1 reverse transcriptase. Termination of processive synthesis on a natural DNA template is influenced by the sequence of the template-primer stem.

During processive DNA synthesis in vitro, the human immunoefficiency virus, type 1 (HIV-1) reverse transcriptase encounters template nucleotide positions at which continued synthesis is difficult. At these positions, the enzyme has a relatively high probability of dissociating from the template, and product molecules of corresponding length accumulate as the incubation proceeds. These positions, which are known as termination sites, could be associated with template secondary structures in some cases, but many termination sites appear to be template sequence-related rather than secondary structure-related. Mechanisms producing these blocks in processive DNA synthesis are not well understood. In this study, to examine further the effects of template sequence on termination, we engineered selected single-base changes in the M13mp2 template, and we found that such changes can influence termination. Several general trends emerged from the study. First, strong termination sites rarely correspond to dATP as the "incoming" substrate opposite template T. Second, the sequence of the template-primer stem is more important for termination than the sequence of the single-stranded template ahead of the primer. Thus, we note the phenomenon of action at a distance: changing sequence at one nucleotide position in the template-primer stem alters termination at other positions, a few nucleotides distant at the primer 3' end. A and C as template bases in the template-primer stem have opposite effects. A is the strongest terminator residue, and C is the weakest terminator residue, followed by G. Since termination sites are produced by reverse transcriptase dissociation from the template-primer, the results suggest that the HIV-1 reverse transcriptase has properties reminiscent of a sequence-specific double-stranded DNA-binding protein in that its binding mechanism can distinguish both base residues and positions in the double-stranded DNA template-primer stem.

Base Sequence↗
PubMed2001

Linkers for improved cleavage of fusion proteins with an engineered alpha-lytic protease.

Addition of an N-terminal fusion partner can greatly aid the expression and purification of a recombinant protein in Escherichia coli. We investigated two genetically engineered proteases designed to remove the fusion partner after the protein of interest has been expressed. Recombinant human insulin-like growth factor-II (hIGF-II) has been produced from E. coli-derived fusion proteins using a novel enzymatic cleavage system that uses a mutant of alpha-lytic protease. Initially, two potential fusion protein linkers were designed, Pro-Ala-Pro-His (PAPH) and Pro-Ala-Pro-Met (PAPM), and were tested as substrates in the form of synthetic dodecapeptides. Using mass spectrometry and reverse-phase HPLC, the position of cleavage was confirmed and the kinetics of synthetic peptide cleavage were examined. Use of the linkers in hIGF-II fusion proteins produced in E. coli was then evaluated. The fusion proteins constructed consist of the first 11 amino acids of porcine growth hormone linked N-terminally to hIGF-II by six amino acids that include the dipeptide Val-Asn followed by a variable tetrapeptide protease cleavage motif. Mass spectrometry and N-terminal sequencing confirmed that proteolytic cleavage of the fusion proteins had occurred at the predicted sites. Using the fusion proteins as substrates, the cleavage of the rationally designed motifs by the alpha-lytic protease mutant was compared. The fusion protein containing the motif PAPM had a k(cat)/K(M) ratio indicating a 1.6-fold preference over the PAPH fusion protein for cleavage by this enzyme. Furthermore, when hIGF-II fusion proteins containing the designed cleavable linkers were processed with the engineered alpha-lytic protease, they gave greatly improved yields of native hIGF-II compared to an analogous fusion protein cleaved by H64A subtilisin. Comparison of the peptide and protein cleavage studies shows that the efficient proteolysis of the cleavage motifs is an inherent property of the designed sequences and is not determined by secondary or tertiary structure in the fusion proteins.

Amino Acid Sequence↗
PubMed2001

Chondrocyte expressed protein-68 (CEP-68), a novel human marker gene for cultured chondrocytes.

In the search for new marker genes suitable to distinguish chondrocytes from osteoblasts and mesenchymal stem cells in culture, we have identified and characterized a novel gene called chondrocyte expressed protein-68 (CEP-68), harbouring an N-terminal leader peptide and an epidermal growth factor-like calcium-binding domain. CEP-68 defines a new family of proteins and complements collagen type II as a new marker for stem-cell-based chondrogenic tissue engineering.

Amino Acid Sequence↗
PubMed1995

Construction of lysine-producing strains by gene disruption and replacement in Brevibacterium divaricatum.

Gene disruption and replacement techniques were applied to block the biosynthesis of threonine and methionine and thus to construct genetically stable lysine producers in a glutamate-producing bacteria, Brevibacterium divaricatum. The homoserine dehydrogenase gene (hom), homoserine kinase gene (thrB) and hom-thrB operon were amplified as 1.8, 1.25 and 2.8 kb fragments from B. divaricatum by polymerase chain reaction (PCR) and cloned in an E. coli-coryneform bacteria shuttle vector, pSUMN18. These genes were disrupted by inserting a kanamycin resistant gene (kan) from pUC4-KISS into the structural genes. Integrative plasmids were constructed and transformed into B. divaricatum. Integrative transformants could be obtained only when the integrative plasmids were constructed from the plasmids which had escaped from the restriction barrier of the hosts. The resulting integrative transformants showed kanamycin resistance and contained no plasmids. About 1-10% of the transformants were auxotrophs. By checking the nutritional requirement, it was found that all of these transformants required threonine and/or homoserine as expected. Southern blot analysis confirmed the integrations, and both single and double crossover homologous recombination mechanisms were proposed to explain the integration and replacement. These auxotrophic integrative transformants which were derived from double crossover events accumulated 1-3% lysine in culture broth only when the added threonine was limited. Integrative transformants which were site-specifically inactivated in hom or hom-thrB genes produced more lysine than did those only inactivated at the thrB gene. These transformants were extremely stable, and the reversion frequency was below 10(-9) per generation. It is suggested that this technique will be useful in the construction of stable auxotrophic mutants.

Actinomycetales↗
PubMed2004

Rational engineering of enzyme stability.

During the past 15 years there has been a continuous flow of reports describing proteins stabilized by the introduction of mutations. These reports span a period from pioneering rational design work on small enzymes such as T4 lysozyme and barnase to protein design, and directed evolution. Concomitantly, the purification and characterization of naturally occurring hyperstable proteins has added to our understanding of protein stability. Along the way, many strategies for rational protein stabilization have been proposed, some of which (e.g. entropic stabilization by introduction of prolines or disulfide bridges) have reasonable success rates. On the other hand, comparative studies and efforts in directed evolution have revealed that there are many mutational strategies that lead to high stability, some of which are not easy to define and rationalize. Recent developments in the field include increasing awareness of the importance of the protein surface for stability, as well as the notion that normally a very limited number of mutations can yield a large increase in stability. Another development concerns the notion that there is a fundamental difference between the "laboratory stability" of small pure proteins that unfold reversibly and completely at high temperatures and "industrial stability", which is usually governed by partial unfolding processes followed by some kind of irreversible inactivation process (e.g. aggregation). Provided that one has sufficient knowledge of the mechanism of thermal inactivation, successful and efficient rational stabilization of enzymes can be achieved.

Biotechnology↗
PubMed2002

Engineering a remarkably low HOMO-LUMO gap by covalent linkage of a strong pi-donor and a pi-acceptor--tetrathiafulvalene-sigma-polynitrofluorene diads: their amphoteric redox behavior, electron transfer and spectroscopic properties.

Novel R3TTF-sigma-A compounds 14, 16 and 19 (R3TTF = trial-kyletrathiafulvalene, sigma = saturated spacer, A = polynitrofluoren-9-dicyano-methylene acceptor) incorporating very strong donor and acceptor moieties have been synthesized by condensation of the corresponding R3TTF-sigma-fluoren-9-one diads with malononitrile. Reversible five-step amphoteric redox behavior has been observed with an extremely low HOMO-LUMO gap (approximately 0.3 eV). For compound 14 a strong EPR signal is observed in the solid state, ascribed to intermolecular complexation: a less intense signal is seen in solution, corresponding to ca. 2% of the molecules existing in a radical form at room temperature. Intramolecular charge transfer in diads 14 and 16 is manifested in strong absorption bands in the near-IR region of their electronic spectra. Spectroelectrochemical data reveal marked electrochromic behavior in the visible and near-IR region of both compounds. The first X-ray crystal structure of a fluorene radical-anion salt is reported, namely the copper salt of 2,4,5,7-tetranitro-9- dicyanomethylenefluorene (1:1 stoichiometry).

Journal Article↗
PubMed1994

Reversal of signal-mediated cellular retention by subunit assembly of human acetylcholinesterase.

The interrelationship between signal-mediated endoplasmic reticulum retention and control of subunit assembly in secreted complex proteins was examined in recombinant 293 cells expressing human acetylcholinesterase (HuAChE). This was achieved by analyzing the mutual effects of co-residing retention and dimerization signals on enzyme secretion by transfected cells. The function of putative signals within the COOH-terminal tetrapeptide CSDL of HuAChE was examined by site-directed mutagenesis. The CSDL tetrapeptide carries the free cysteine (Cys-580) involved in subunit assembly, yet it fails to function as a KDEL-type retention signal. This was demonstrated by mutations that increase similarity to the canonical retention signal (substitution of CSDL by KSDL) or those that deviate from it (substitution to CSAL). Cells expressing both types of mutants exhibited cell-associated HuAChE levels identical to that of wild type enzyme. Appendage of an engineered KDEL retention signal to a dimerization-impaired HuA-ChE subunit (the C580A mutant) resulted in intracellular retention of large amounts of fully active enzyme not prone to proteolytic degradation. On the other hand, attachment of KDEL to a native, dimerization-competent HuAChE polypeptide did not lead to intracellular retention and allowed efficient secretion of enzyme to the cell growth medium. Yet, appendage of KDEL to the native HuAChE led to some retardation in the transport of enzyme molecules through the Golgi apparatus, as manifested by increase in cellular population of endo H-resistant dimers, when compared with wild type enzyme. Taken together, these results indicate (alpha) that sub-unit dimerization mediated by the COOH-terminal cysteine of HuAChE can reverse the signal-mediated retention by masking recognition of KDEL by its cognate receptor and (b) that the native sequences of the acetylcholinesterase subunit polypeptide do not appear to function as a coupled retention/dimerization signal in the control of secretion of assembled enzyme molecules.

Acetylcholinesterase↗
PubMed2002

Infectious cDNA clone of the epidemic west nile virus from New York City.

We report the first full-length infectious clone of the current epidemic, lineage I, strain of West Nile virus (WNV). The full-length cDNA was constructed from reverse transcription-PCR products of viral RNA from an isolate collected during the year 2000 outbreak in New York City. It was cloned into plasmid pBR322 under the control of a T7 promoter and stably amplified in Escherichia coli HB101. RNA transcribed from the full-length cDNA clone was highly infectious upon transfection into BHK-21 cells, resulting in progeny virus with titers of 1 x 10(9) to 5 x 10(9) PFU/ml. The cDNA clone was engineered to contain three silent nucleotide changes to create a StyI site (C to A and A to G at nucleotides [nt] 8859 and 8862, respectively) and to knock out an EcoRI site (A to G at nt 8880). These genetic markers were retained in the recovered progeny virus. Deletion of the 3'-terminal 199 nt of the cDNA transcript abolished the infectivity of the RNA. The plaque morphology, in vitro growth characteristics in mammalian and insect cells, and virulence in adult mice were indistinguishable for the parental and recombinant viruses. The stable infectious cDNA clone of the epidemic lineage I strain will provide a valuable experimental system to study the pathogenesis and replication of WNV.

Animals↗
PubMed2006

Characterization of TGF-beta-regulated interleukin-8 expression in human prostate cancer cells.

BACKGROUND: Interleukin (IL)-8 and transforming growth factor (TGF)-beta1 are overexpressed in advanced prostate cancer. The purpose of this study was to investigate TGF-beta1-regulated IL-8 expression in prostate cancer cells. METHODS: TGF-beta receptor expression was evaluated by real-time reverse-transcription PCR (RT-PCR) and Western blotting. TGF-beta1-regulated IL-8 expression was determined by real-time RT-PCR, enzyme-linked immunoabsorbance assay (ELISA), nuclear run-on, and IL-8 promoter reporter assay. RESULTS: PC-3MM2 cells expressed type I and type II TGF-beta receptors (TbetaRI and TbetaRII). LNCaP cells expressed significantly lower level of TbetaRII. Constitutive expression of IL-8 was detected in PC-3MM2 cells and LNCaP cells engineered with TbetaRII (LNCaP-TbetaRII). TGF-beta1 stimulated IL-8 expression in dose- and time-dependent manners, which was blocked by cycloheximide (CHX) and actinomycin D (ActD). The nuclear run-on and IL-8 luciferase reporter assays show that TGF-beta1 activated IL-8 gene transcription. CONCLUSIONS: TGF-beta1 signaling regulates IL-8 expression in prostate cancer cells and may contribute to the overexpression of IL-8 in human prostate cancer.

Activin Receptors, Type I↗
PubMed1998

Redesign of choline acetyltransferase specificity by protein engineering.

Since the development of site-directed mutagenesis techniques over 15 years ago (Zoller, M. J., and Smith, M. (1982) Nucleic Acids Res. 10, 6487-6500), it has been a goal of protein engineering to utilize the procedure to redesign existing enzyme structures to produce proteins with altered or novel catalytic properties. To date, however, the more successful achievements have relied exclusively on the availability of three-dimensional protein structure maps to direct the redesign strategies. Presently, such maps are unavailable for choline acetyltransferase and carnitine acetyltransferase, enzymes that catalyze the reversible transfer of an acetyl group from acetyl-CoA to choline and L-carnitine, respectively. A more empirical approach, based on cross-referencing substrate structure comparisons with protein alignment data, was used to redesign choline acetyltransferase to accommodate L-carnitine as an acceptor of the acetyl group. A mutant choline acetyltransferase that incorporates four amino acid substitutions from wild type, shows a substantial increase in catalytic efficiency (kcat/Km) toward L-carnitine (1,620-fold) and shifts the catalytic discrimination between choline and L-carnitine by >390,000 in favor of the latter substrate. These dramatic alterations in catalytic function demonstrate that significant success in protein redesign can be achieved in the absence of three-dimensional protein structure data.

Amino Acid Sequence↗
PubMed2005

Composition, toxicity, and mutagenicity of particulate and semivolatile emissions from heavy-duty compressed natural gas-powered vehicles.

Particulate matter (PM) and vapor-phase semivolatile organic compounds (SVOC) were collected from three buses fueled by compressed natural gas. The bus engines included a well-functioning, conventional engine; a "high emitter" engine; and a new technology engine with an oxidation catalyst. Chemical analysis of the emissions showed differences among these samples, with the high emitter sample containing markers of engine oil constituents. PM + SVOC samples were also collected for mutagenicity and toxicity testing. Extraction efficiencies from the collection media were lower than for similarly collected samples from gasoline or diesel vehicles. Responses to the recovered samples were compared on the basis of exhaust volume, to incorporate the emission rates into the potency factors. Mutagenicity was assessed by Salmonella reverse mutation assay. Mutagenicity was greatest for the high emitter sample and lowest for the new technology sample. Metabolic activation reduced mutagenicity in strain TA100, but not TA98. Toxicity, including inflammation, cytotoxicity, and parenchymal changes, was assessed 24 h after intratracheal instillation into rat lungs. Lung responses were generally mild, with little difference between the responses to equivalent volumes of emissions from the normal emitter and the new technology, but greater responses for the high emitter. These emission sample potencies are further compared on the basis of recovered mass with previously reported samples from normal and high-emitter gasoline and diesel vehicles. While mutagenic potencies for the CNG emission samples were similar to the range observed in the gasoline and diesel emission samples, lung toxicity potency factors were generally lower than those for the gasoline and diesel samples.

Air Pollutants↗
PubMed1991

Molecular analysis of primitive hematopoietic cell proliferation control mechanisms.

Cells at two distinct early stages in the development of mature human blood cells from primitive totipotent hematopoietic stem cells can now be defined and quantitated by separate in vitro assays. Current evidence suggests that most, if not all, colony-forming cells--that is, cells that give rise to colonies of mature progeny within one to three weeks in semisolid culture systems, represent an intermediate stage of hematopoietic progenitor. These cells are not self-sustaining; if they are used to initiate hematopoiesis on competent marrow stromal layers, they rapidly disappear as they differentiate or die. However, clonogenic cells can be generated in such cultures from another cell type over a period of four to eight weeks. We have, therefore, assigned the term long-term culture initiating cell (LTC-IC) to this latter type of clonogenic precursor cell. The production and differentiation of cells in both of these compartments in LTC are dependent on, and regulated by, nonhematopoietic "stromal" cells that form a heterogeneous adherent layer in which close-range interactions with hematopoietic cells take place. The use of separate endpoints to monitor the maintenance, differentiation, and reversible activation or arrest of cycling of these cells has recently revealed different molecular mechanisms regulating their respective functions. However, an important common feature appears to be the relative local concentration of positive and negative regulators to which the target hematopoietic cell is exposed. Both gene expression and growth factor release measurements as well as results obtained using genetically engineered stroma and repeated soluble growth factor addition implicate G-CSF as an endogenous positive regulator of primitive hematopoietic cells. Similarly, gene expression, factor production, factor addition, and neutralizing antibody experiments implicate TGF-beta as an endogenous inhibitor of primitive hematopoietic cells.

Bone Marrow Cells↗
PubMed2001

Salivary enhancement: current status and future therapies.

Saliva provides the principal protective milieu for teeth by modulating oral microbial ecosystems and reversing the initial phases of caries development. Patients with inadequate salivary function are at increased risk for dental decay. Therefore, it is likely that therapies that increase overall fluid output of these individuals will reverse early carious lesions. The most common causes of salivary dysfunction are medication usage, Sjögren's syndrome, and damage of salivary parenchyma during therapeutic irradiation. For patients with remaining functional acinar tissue, treatment with the parasypathomimetic secretogogues pilocarpine and Cevimeline may provide relief. However, these medications do not benefit all patients. The possibilities of using gene therapy and tissue engineering to develop treatments for those with severe salivary dysfunction are discussed.

Animals↗
PubMed2026

Engineering Protein Stability with Small Molecules: A Review of the ecDHFR Destabilizing Domain System.

The E. coli dihydrofolate reductase (ecDHFR) destabilizing domain (DD) is a versatile post-translational tool for the conditional control of protein stability via ligand-induced stabilization. In this system, a DD-tagged protein is rapidly degraded by the proteasome unless stabilized by the antibiotic trimethoprim (TMP), allowing for conditional control of protein abundance. The ecDHFR-DD system has been successfully applied across diverse biological systems, including yeast, invertebrate models such as Drosophila, and mammalian cells, to study a broad spectrum of cellular and developmental processes. Compared with DNA- and RNA-based regulatory approaches, post-translational systems offer faster response times and more precise control, making them valuable for processes that require tight, reversible regulation. In this review, we synthesize current knowledge on the mechanisms, performance, and optimization of the ecDHFR-DD system across organisms and evaluate its advantages and limitations relative to most conditional gene expression systems. We also highlight emerging opportunities for applying the system across diverse areas, ranging from functional genomics and synthetic biology to biomedical research. Additionally, we discuss its potential application in applied biological systems, such as pest and vector management, positioning the ecDHFR-DD system as a broadly applicable platform for the precise and tunable control of protein function across diverse disciplines.

Tetrahydrofolate Dehydrogenase↗