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PubMed2001

Identification of differentially expressed genes in rat hippocampus after transient global cerebral ischemia using subtractive cDNA cloning based on polymerase chain reaction.

BACKGROUND AND PURPOSE: The purpose of this study is to identify new molecules that play important roles in the phenomena that occur in the hippocampus after transient global cerebral ischemia, as clues to better understanding of the mechanisms. METHODS: A subtractive cDNA library was established by suppression subtractive hybridization of rat hippocampal tissues after transient global cerebral ischemia. With differential screening of the library, upregulated fragments were identified. The mRNA expression levels of selected genes were measured with semiquantitative reverse transcriptase polymerase chain reaction (PCR). RESULTS: Among more than 100 isolated fragments, approximately half were determined to be identical to known sequences. The rest showed high homology to known sequences, and only 2 did not exhibit homology to any known sequences. The expression of 5 genes identified in this study increased in 24 hours after ischemia to a level twice as high as that in sham-operated controls. These included furin, prosaposin, synaptotagmin IV, heat shock protein 105, and the neutral and basic amino acid transporter (NBAT). The increases in the mRNA expression levels of the genes except NBAT, as revealed by semiquantitative reverse transcription PCR, were statistically significant at both 6 and 24 hours after ischemia. CONCLUSIONS: Genes isolated are thought to be associated with production of proteins necessary for degeneration, neuroprotection, and reconstruction of neurons. How the expression of these genes relates to functional changes after ischemia remains to be determined. PCR-based subtractive cDNA cloning is demonstrated to be a useful tool for analyzing in vivo gene expression in animal ischemia models.

Amino Acid Transport Systems, Basic↗
PubMed1975

Sites of biological methylation of proteins in cultured chick muscle cells.

The methylation of myosin and other proteins has been studied using primary cultures of 12-day-old embryonic chick leg muscle. The methyl group of [Me-3H] methionine is incorporated into basic amino acid residues with the formation of Nepsilon-monomethyllysine, Nepsilon-dimethyllysine, Nepsilon-trimethyllysine, 3-methylhistidine, NG-monomethylarginine, and NG-dimethylarginine which are isolated from acid hydrolysates of purified myosin, and of proteins from polysomes and from the cytosol of the cultured muscle cells. In the presence of 0.1 mM cycloheximide, incorporation of [Me-3H] methionine into the polysome-bound proteins was decreased to 16.3% of control levels with no change in the pattern of incorporation into the basic amino acid residues, although protein synthesis was inhibited 97.5%. When protein synthesis was allowed to resume in such cultures by the removal of cycloheximide, polypeptides containing labeled N-methylated residues were released from polysomes into the soluble fraction. Polypeptides containing N-methylated amino acids were also released from polysomes following treatment with 2 mM puromycin. Peptidyl-tRNA, isolated from ribosomes after exposure of cultures to [Me-3H] methionine, contained labeled N-methylated amino acids. When [Me-3H] methionine was incorporated in the presence of cycloheximide, the isolated peptidyl-tRNA still contained N-methylated amino acids although the amount of methylation was 22.4% of control levels. These experiments demonstrate that N-methylation of basic amino acid residues in proteins may occur while the polypeptide is still being synthesized on the ribosome. In addition, N-methylation can occur on the nascent polypeptides in the absence of protein synthesis.

Amino Acids↗
PubMed1981

Purification and properties of a bovine brain thyrotropin-releasing-factor deamidase. A post-proline cleaving enzyme of limited specificity.

A bovine brain thyrotropin-releasing-factor (thyroliberin) deamidase has been purified 1100-fold to apparent homogeneity. Molecular weight estimates by gel filtration and sodium dodecylsulfate gel electrophoresis indicate that the enzyme consists of a single polypeptide chain of molecular weight of about 62 000-65 000. The enzyme is inactivated by sulfhydryl blocking agents. Serine proteinase inhibitors, phenylmethanesulfonyl fluoride and benzamidine, have no effect. Besides thyroliberin, the enzyme hydrolyzes peptide bonds involving the carboxyl group of proline residues in luliberin, tuftsin, angiotensin II, melanotropin, and neurotensin. Oxytocin, vasopressin, and bradykinin are not cleaved; they are, however, strong competitive inhibitors of thyroliberin deamidation. The specificity studies indicate that the enzyme is a "post-proline cleaving enzyme" which hydrolyzes peptides of the general structure, Yaa-Pro-Xaa, in which Xaa = amino acid, peptide, or amide (not Pro), and Yaa = N-blocked basic amino acid or a peptide sequence in which the C-terminal residue (i.e. the residue prior to Pro) is a basic amino acid such as His, Lys, or Arg. The enzyme is compared to other post-proline cleaving enzymes.

Amidohydrolases↗
PubMed1988

Synthetic peptide substrates as models to study a pro-ocytocin/neurophysin converting enzyme.

The selectivity and mechanism of processing at paired basic amino acids in hormone precursors was studied on several analogues of the (1-20)-aminoterminal domain of the ocytocin/neurophysin precursor in a cleavage assay by an endoprotease partially purified from bovine pituitary secretory granules. Peptide analogues with amino acid substitutions in, and around, the basic doublet were synthesized and used as substrates. The data obtained demonstrate the strict requirement of the processing enzyme for basic amino acids in tandem within a possibly preferred conformation which may be highly conserved in the aminoterminal domain of this hormone precursor.

Animals↗
PubMed1995

Amino acid transport systems required for diazotrophic growth in the cyanobacterium Anabaena sp. strain PCC 7120.

Uptake of 16 amino acids by the filamentous, heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120 was characterized with regard to kinetic parameters of transport, intracellular accumulation of the transported amino acids, and sensitivity of the transport process to energy metabolism inhibitors. Mutants resistant to certain toxic analogs of some amino acids were isolated that were impaired in amino acid transport. Results obtained in this study, together with those reported previously (A. Herrero and E. Flores, J. Biol. Chem. 265:3931-3935, 1990), suggest that there are at least five amino acid transport systems in strain PCC 7120: one high-affinity, active system for basic amino acids; one low-affinity, passive system for basic amino acids; two high-affinity, active systems with overlapping, but not identical, specificities for neutral amino acids; and one putative system for acidic amino acids. Some of the amino acid transport mutants were impaired in diazotrophic growth. These mutants were unable to develop a normal percentage of heterocysts and normal nitrogenase activity in response to nitrogen stepdown. Putative roles for the amino acid transport systems in uptake of extracellular amino acids, recapture of amino acids that have leaked from the cells, and intercellular transfer of amino acids in the filaments of Anabaena sp. strain PCC 7120 are discussed.

Amino Acids↗
PubMed1992

Characterization of nuclear targeting signal of hepatitis delta antigen: nuclear transport as a protein complex.

Hepatitis delta antigen (HDAg) is the only protein encoded by hepatitis delta virus (HDV). HDAg has been demonstrated in the nuclei of HDV-infected hepatocytes, and its nuclear transport may be important for the replication of HDV RNA. In this report, we investigated the mechanism of nuclear transport of HDAg. By expressing fusion proteins consisting of the different portions of HDAg and alpha-globin, we have identified a nuclear localization signal (NLS) within the N-terminal one-third of HDAg. It consists of two stretches of basic amino acid domains separated by a short run of nonbasic amino acids. Both of the basic domains are necessary for the efficient nuclear transport of HDAg. The nonbasic spacer amino acids could be removed without affecting the nuclear targeting of HDAg significantly. Thus, the HDAg NLS belongs to a newly identified class of NLS which consists of two discontiguous stretches of basic amino acids. This NLS is separated from a stretch of steroid receptor NLS-like sequence, which is also present but not functioning as an NLS, in HDAg. Furthermore, we have shown that subfragments of HDAg which do not contain the NLS can be passively transported into the nucleus by a trans-acting full-length HDAg, provided that these subfragments contain the region with a leucine zipper sequence. Thus, our results indicate that HDAg forms aggregates in the cytoplasm and that the HDAg oligomerization is probably mediated by the leucine zipper sequence. Therefore, HDAg is likely transported into the nucleus as a protein complex.

Amino Acid Sequence↗
PubMed1993

Deduced amino acid sequences at the haemagglutinin cleavage site of avian influenza A viruses of H5 and H7 subtypes.

The amino acid sequences at the haemagglutinin cleavage sites of 9 avian influenza A viruses of H5 subtype (5 high and 4 low pathogenicity for chickens) and 21 of H7 subtype (13 high and 8 low pathogenicity for chickens) were determined by direct RNA sequencing, PCR amplification sequencing or both. None of the viruses of low pathogenicity had multiple basic amino acids at the cleavage site. All highly pathogenic viruses had an insert of basic amino acids at the cleavage site, except A/chicken/Scotland/59 (H5N1) for which the multiple basic amino acids appeared as substitutions and not insertions. All highly pathogenic viruses examined conformed to the amino acid motif of R-X-R/K-R at the cleavage site which is considered to be essential for high pathogenicity in chickens, with the notable exception of highly pathogenic virus A/turkey/England/50-92/91 (H5N1) which had the sequence R-K-R-K-T-R adjacent to the cleavage site.

Amino Acid Sequence↗
PubMed1997

Determination of the specific substrate sequence motifs of protein kinase C isozymes.

Protein kinase C (PKC) family members play significant roles in a variety of intracellular signal transduction processes, but information about the substrate specificities of each PKC family member is quite limited. In this study, we have determined the optimal peptide substrate sequence for each of nine human PKC isozymes (alpha, betaI, betaII, gamma, delta, epsilon, eta, mu, and zeta) by using an oriented peptide library. All PKC isozymes preferentially phosphorylated peptides with hydrophobic amino acids at position +1 carboxyl-terminal of the phosphorylated Ser and basic residues at position -3. All isozymes, except PKC mu, selected peptides with basic amino acids at positions -6, -4, and -2. PKC alpha, -betaI, -betaII, -gamma, and -eta selected peptides with basic amino acid at positions +2, +3, and +4, but PKC delta, -epsilon, -zeta, and -mu preferred peptides with hydrophobic amino acid at these positions. At position -5, the selectivity was quite different among the various isozymes; PKC alpha, -gamma, and -delta selected peptides with Arg at this position while other PKC isozymes selected hydrophobic amino acids such as Phe, Leu, or Val. Interestingly, PKC mu showed extreme selectivity for peptides with Leu at this position. The predicted optimal sequences from position -3 to +2 for PKC alpha, -betaI, -betaII, -gamma, -delta, and -eta were very similar to the endogenous pseudosubstrate sequences of these PKC isozymes, indicating that these core regions may be important to the binding of corresponding substrate peptides. Synthetic peptides based on the predicted optimal sequences for PKC alpha, -betaI,-delta, -zeta, and -mu were prepared and used for the determination of Km and Vmax for these isozymes. As judged by Vmax/Km values, these peptides were in general better substrates of the corresponding isozymes than those of the other PKC isozymes, supporting the idea that individual PKC isozymes have distinct optimal substrates. The structural basis for the selectivity of PKC isozymes is discussed based on residues predicted to form the catalytic cleft.

Amino Acid Sequence↗
PubMed2006

Gelatin-based plasma expander effectively reduces renal uptake of 111In-octreotide in mice and rats.

UNLABELLED: 111In-Diethylenetriaminepentaacetic acid-octreotide generally is used for the scintigraphic imaging of neuroendocrine and other somatostatin receptor-positive tumors. On the basis of the successful targeting of octreotide, radiolabeled somatostatin analogs, such as 90Y-(1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid [DOTA])0-Tyr3-octreotide and 177Lu-DOTA0-Tyr3-octreotate, were developed for peptide receptor radionuclide therapy. However, the maximum tolerated doses of these analogs are limited because of the high and persistent renal uptake that leads to relatively high radiation doses in the kidneys. Renal uptake can be reduced by coinfusion of basic amino acids or polypeptides. However, high doses of basic amino acids can induce severe side effects. It was reported that the infusion of gelatin-based plasma expanders resulted in increased low-molecular-weight proteinuria, suggesting that these plasma expanders interfere with the tubular reabsorption of peptides and proteins. In the present study, we analyzed the effects of several plasma expanders on the renal uptake of 111In-octreotide in rats and mice. METHODS: Wistar rats and BALB/c mice were injected with 0.5 or 0.1 mL of plasma expander, respectively. Thereafter, the animals received 111In-octreotide intravenously. Animals were killed at 20 h after the injection of the radiopharmaceutical. Organs were dissected, and the amount of radioactivity in the organs and tissues was measured. RESULTS: The administration of 20 mg of Gelofusine in rats or 4 mg in mice was as effective in reducing the renal uptake of 111In-octreotide as the administration of 80 or 20 mg of lysine in rats or mice, respectively, without reducing 111In-octreotide uptake in receptor-positive organs. Plasma expanders based on starch or dextran had no effect on the renal uptake of 111In-octreotide. CONCLUSION: The gelatin-based plasma expander Gelofusine significantly reduced the kidney uptake of 111In-octreotide as effectively as did lysine. Because Gelofusine is a well-known and generally used blood volume substitute that can be applied safely without the induction of toxicity, evaluation of this compound for its potential to reduce the kidney uptake of radiolabeled peptides in patients is warranted.

Animals↗
PubMed1980

Muscle and plasma amino acids after injury: hypocaloric glucose vs. amino acid infusion.

This study examines the effect of three different hypocaloric diets on the patterns of muscle and plasma amino acids in patients undergoing total hip replacement. Group I (seven patients) received 90 g/day of glucose, Group II (seven patients) received 70 g/day of amino acids, Group III (eight patients) received both 90 g of glucose and 70 grams of amino acids per day. Utilizing the percutaneous biopsy technique of Bergström, free amino acid patterns in muscle and plasma were analyzed pre- and postoperatively (day 4). The postoperative pattern of amino acids was characterized by elevated levels in muscle and plasma of the branched chain amino acids, phenylalanine, tyrosine and methionine. There was a marked decrease in muscle glutamine and smaller decreases in the basic amino acids in both muscle and plasma. Muscle:plasma concentration ratios increased for the neutral amino acids, decreased for glutamine and the basic amino acids and were unchanged for the acidic amino acids. The patterns seen after hip replacement are almost identical to those seen after colectomy or accidental injury. There was little effect of diet on amino acid concentrations in muscle. In plasma, concentrations of leucine, isoleucine, valine and proline were higher in Group II in the absence of glucose intake, than in the other groups. Lysine was lower in Group I with no amino acid intake than in the other groups. Thus, there is a unique amino acid pattern associated with operative trauma which is relatively unaffected by hypocaloric, intravenous nutrition.

Amino Acids↗
PubMed1986

Purification and immunochemical properties of a protein antigen from serotype g Streptococcus mutans.

A proteinaceous antigen (PAg) was purified from the culture supernatant of Streptococcus mutans 6715 (serotype g) by ultrafiltration, ammonium sulfate precipitation, DEAE-Sephacel ion-exchange chromatography, Phenyl-Sepharose CL-4B hydrophobic chromatography, and subsequent Sephacryl S-300 gel filtration. A yield of 0.1 mg of PAg was obtained from a liter of culture supernatant. The isoelectric point and molecular weight of PAg were pH 4.6 and 210,000, respectively. It contained 35% sugar, which was identified as glucose by gas-liquid chromatography. Amino acid analysis revealed that PAg contains 28% acidic and 11% basic amino acid residues. PAg retained its antigenicity after heating at 80 C for 10 min in deionized water, or after treatment with 0.1 M HC1 or 0.1 M NaOH at 37 C for 1 hr. Immunodiffusion and immunoelectrophoresis analyses revealed that PAg is serologically distinct from other cell-surface antigens such as serotype-specific polysaccharide and lipoteichoic acid. A cross-reaction between PAg and a protein antigen similarly prepared from serotype c S. mutans was observed in immunodiffusion tests.

Amino Acids↗
PubMed1993

Ultrastructure of phosphotungstic acid (PTA) positive deposits in the hippocampus of senile demented patients.

To perform a quantitative investigation on synaptic ultrastructural features in the human hippocampus in normal old and senile demented patients we stained our tissue samples by means of the ethanol-phosphotungstic acid (E-PTA) preferential technique. In addition to the synaptic contact zones, we found that structures similar to neurofibrillary tangles (NFT) and senile plaques (SP) were remarkably positive to our staining procedure, while the background was faintly electron lucent. On the basis of the E-PTA staining properties and specificity, we support that the reactive sites of these positive structures are represented by basic amino acids. The recently demonstrated presence of 4 basic amino acids (1 arginine, 3 histidine) in the cleaved fragment of the amyloid precursor protein (APP) suggest us to hypothesise that this APP portion may represent the common constitutive element of the many morphologically different alterations found in the brains of senile demented patients.

Aged↗
PubMed2002

Analysis and characterization of phosphinic pseudopeptides by capillary zone electrophoresis.

Capillary zone electrophoresis (CZE) was applied to analysis and characterization of phosphinic pseudopeptides with the general structure N-Ac-Val-Ala(psi)(PO2(-)-CH(2)) Leu-Xaa-NH(2), where Xaa represents one of 20 proteinogenic amino acid residues. Pseudopeptides containing neutral or acidic amino acid residues in position Xaa were analyzed as anions in weakly alkaline (pH 8.1) Tris-Tricine background electrolyte (BGE), pseudopeptides with basic amino acid residues in position Xaa were analyzed as cations in acid BGEs (Tris-phosphate buffers). Acidity of phosphinic acid moiety in peptides with basic amino acid residues was determined from the dependence of effective mobility of these peptides on pH in the acid pH region (pH 1.4-2.8). Additionally, separation of diastereomers of some peptides was achieved.

Electrophoresis, Capillary↗
PubMed1982

Primary structure of Escherichia coli ribosomal protein S1 and features of its functional domains.

The complete covalent structure of ribosomal protein S1 of Escherichia coli has been determined and predictions made of its secondary structure. Protein S1 (E. coli MRE 600) is a single-chain, acidic protein with 557 amino acid residues of the composition Asp43, Asn23, Thr25, Ser25, Glu60, Gln14, Pro10, Gly48, Ala48, Val67, Met6, Ile30, Leu45, Tyr6, Phe17, His8, Lys43, Arg30, Trp7, Cys2 and an Mr of 61159. The two -SH groups of S1 are located in the central region of the chain at positions 292 and 349, the latter being the reactive group whose modification results in the reported loss of the nucleic-acid-unfolding ability of S1. The central region also contains the majority of the tryptophan, histidine and methionine residues of S1 and is predicted to have a secondary structure dominated by beta-sheets and turns. A direct proof for the location of the nucleic-acid-binding domain of S1 in the central region has recently been obtained [Subramanian et al. (1981) Eur. J. Biochem. 119, 245-249]. The N-terminal region of S1, which contains the ribosome-binding domain has a relatively high predicted alpha-helix content and no preponderance of basic amino acids. The facile trypsin-sensitive site in S1 is located at Arg-171, approximately at the border between the N-terminal and central regions. The acidic and basic amino acids of S1 (32.8% of all residues) are distributed throughout the chain, often in small clusters of between two and six residues. The amino acid sequence of S1 contains three 24-residue stretches with strong internal homology. Two of the stretches are located in the central, RNA-binding region, suggesting a possible role in the RNA-binding and helix-destabilizing functions of S1. A fragment of Mr 10(4) from the central region of S1 gives an anomalously high apparent Mr by dodecylsulfate gel electrophoresis, indicating a stable structural element therein and accounting for the apparent high Mr of S1 as determined by gel electrophoresis.

Amino Acid Sequence↗
PubMed1989

Amino Acid and Peptide uptake in the scutella of germinating grains of barley, wheat, rice, and maize.

Scutella separated from germinating grains of barley (Hordeum vulgare L.), wheat (Triticum aestivum L.), rice (Oryza sativa L.), and maize (Zea mays L.) took up the four amino acids and the three peptides tested from incubation media. The uptake of amino acids by wheat scutella was similar to that of barley scutella and was via at least four uptake systems: two nonspecific amino acid uptake systems, one system specific for proline, and another system specific for basic amino acids. The scutellum of rice apparently has two nonspecific systems and a system specific for the basic amino acids, but the proline-specific system is lacking. The scutellum of maize seems to have the same systems as the scutellum of rice, but one (or both) of the nonspecific systems differs from that of the other species studied in taking up arginine only slowly. No great differences were observed in the uptake of peptides in the four species studied. The rates of uptake of different amino acids and peptides were of the same order of magnitude in the four cereals. The fact that carboxypeptidase activities in the endosperms of wheat and barley are 20-to 100-fold higher than those in rice and maize, does thus not seem to be reflected in the uptake properties of the scutella.

Journal Article↗
PubMed1997

Genetic analysis of the phi X174 DNA binding protein.

The phi X174 J protein is 37 amino acids in length and contains 12 basic residues. There are no acidic amino acids in the protein. The basic residues are concentrated in two clusters in the N-terminus which are separated by a proline-rich region. To investigate the morphogenetic functions of the J protein and possible mechanisms by which it may bind DNA, a genetic analysis was conducted. Lysine --> leucine and arginine --> leucine substitutions were generated within the basic amino acid clusters. At least three substitutions were required to eliminate viability in vivo. Lethal mutants with three or four substitutions exhibit dominant lethal phenotypes, indicating that the mutant proteins retain enough function to interfere with productive assembly. In cells infected with a dominant lethal mutant, noninfectious packaged particles were produced. Infectivity can be restored by second-site suppressors in the viral coat protein which disrupt polar interactions atop the threefold axis of symmetry in the capsid. The viability of strains containing compensating frameshift mutations within the proline-rich region suggests that only the proline residues in this segment are critical for efficient function.

Amino Acid Sequence↗
PubMed1996

Substitution of specific amino acids in insulin-like growth factor (IGF) binding protein 5 alters heparin binding and its change in affinity for IGF-I response to heparin.

Heparin binding to insulin-like growth factor (IGF)-binding protein 5 (IGFBP-5) leads to a 17-fold decrease in its affinity for IGF-I, and a region that contains several basic amino acids (Arg201-Arg218) may be involved in this affinity shift. In the present study, mutagenesis was used to analyze the effect of substitutions for basic amino acids in the Arg201-Arg218 region of IGFBP-5 on heparin-binding and the heparin-induced affinity shift. Nine mutant forms were prepared. Their association constants (Ka) for IGF-I were similar to native IGFBP-5. When 10 microg/ml of heparin was added, the Ka of native IGFBP-5 decreased 17-fold, and the Ka of the K134A/R136A mutant decreased 16-fold. In contrast, substitutions for specific basic amino acids in the Arg2O1-Arg218 region decrease the affinity shift to 1.1-3.2-fold. Lys 211 was especially important. When a mutant containing that single substitution was tested, heparin caused only a 2.5-fold reduction in IGF-I affinity. Affinity cross-linking studies showed that heparin was equipotent in inhibiting the formation of 125I-IGF-I-K134A/Rl36A mutant complexes compared to native IGFBP-5. In contrast, heparin had minimal effects on the formation of complexes between 125I-IGF-I and the other mutants. The heparin-binding activity of each mutant was determined. Four mutants, R201A/K202N, K202A/K206A/R207A, R201A/K202N/K206N/K208N, and K211N/R214A/K217A/R218A, had reduced heparin binding compared to native IGFBP-5. The other five mutants, including the K21IN mutant, showed no change in heparin binding. The four mutants with reduced heparin binding could be dissociated from heparin-Sepharose with much lower NaCl concentrations, indicating that they had reduced affinity. These findings suggest that Arg201 Lys202, LysS206, and Arg214 are important for heparin binding. In contrast, LyS211 is not important for the binding of IGFBP-5 to heparin, but substitution for it reduced the heparin-induced affinity shift.

Affinity Labels↗
PubMed2005

Nucleic acid binding property of the gene products of rice stripe virus.

GST fusion proteins of the six gene products from RNAs 2,3 and 4 of the tenuivirus, Rice stripe virus (RSV), were used to study the nucleic acid binding activities in vitro. Three of the proteins, p3, pc3 and pc4, bound both single- and double-stranded cDNA of RSV RNA4 and also RNA3 transcribed from its cDNA clone, while p2, pc2-N (the N-terminal part of pc2) nor p4 bound the cDNA or RNA transcript. The binding activity of p3 is located in the carboxyl-terminus amino acid 154-194, which contains basic amino acid rich beta-sheets. The acidic amino acid-rich amino-terminus (amino acids 1-100) of p3 did not have nucleic acid binding activity. The related analogous gene product of the tenuivirus, Rice hoja blanca virus, is a suppressor of gene silencing and the possibility of the nucleic acid binding ability of RSV p3 being associated with this property is discussed. The C-terminal part of the RSV nucleocapsid protein, which also contains a basic region, binds nucleic acids, which is consistent with its function. The central and C-terminal regions of pc4 bind nucleic acid. It has been suggested that this protein is a cell-to-cell movement protein and nucleic acid binding would be in accord with this function.

Amino Acid Sequence↗