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PubMed2003

Different and divergent regulation of the KIR2DL4 and KIR3DL1 promoters.

The killer Ig-like receptors (KIR) are a family of highly related MHC class I receptors that show extreme genetic polymorphism both within the human population and between closely related primate species, suggestive of rapid evolutionary diversification. Most KIR are expressed in a variegated fashion by the NK population, giving rise to an NK repertoire of specificities for MHC class I. We compared the promoter for KIR3DL1, which exhibits variegated gene expression, with that for KIR2DL4, which is expressed by all NK cell clones. Maximum transcriptional activity of each was encoded within approximately 270 bp upstream of the translation initiation codon. The KIR2DL4 promoter drove reporter gene expression only in NK cells, while the KIR3DL1 promoter was active in a range of cell types, suggesting that the latter requires other regulatory elements for physiological expression. In NK cells, reporter gene expression driven by the KIR2DL4 promoter was greater than that driven by the KIR3DL1 promoter. DNase I footprinting revealed that transcription factor binding sites differ between the two promoters. The data indicate that while the promoters of these two KIR genes share 67% nucleotide identity, they have evolved distinct properties consistent with different roles in regulating the generation of NK repertoire.

Base Composition↗
PubMed2003

C/EBP alpha and Ets protein family members regulate the human myeloid IgA Fc receptor (Fc alpha R, CD89) promoter.

Fc alpha R (CD89), the FcR for IgA, is expressed exclusively in myeloid cells, including monocytes/macrophages, neutrophils, and eosinophils, and is thought to mediate IgA-triggered cellular functions in immunity. Here we demonstrate that the Fc alpha R 5'-flanking region from -102 to -64 relative to the ATG translation initiation codon is essential for promoter activity and contains two functional binding motifs for C/EBP and Ets family members at -74 and -92, respectively. EMSAs and cotransfection experiments show that C/EBP alpha acts as a major activator of the Fc alpha R promoter at least in immature myeloid cells. In addition, we found two additional functional targets of C/EBP alpha at -139 and -127. On the other hand, the Fc alpha R Ets binding motif could bind Elf-1 and mediate the trans-activation by cotransfected Elf-1, but a major component of the complex forming on this site appears to be an unidentified Ets-like nuclear protein that is preferentially detected in cells of hemopoietic origin. Furthermore, separation of the C/EBP and Ets binding sites reduces Fc alpha R promoter activity, suggesting some functional interaction between these factors. As the in vivo role of Fc alpha R is still incompletely defined, these findings reveal the features controlling the Fc alpha R promoter in myeloid lineage and provide a foundation for clarifying regulatory mechanisms of Fc alpha R gene expression associated with its potential roles.

5' Untranslated Regions↗
PubMed1999

Structure and functions of human oxysterol 7alpha-hydroxylase cDNAs and gene CYP7B1.

Oxysterol 7alpha-hydroxylase has broad substrate specificity for sterol metabolites and may be involved in many metabolic processes including bile acid synthesis and neurosteroid metabolism. The cloned human oxysterol 7alpha-hydroxylase (CYP7B1) cDNA encodes a polypeptide of 506 amino acid residues that shares 40% sequence identity to human cholesterol 7alpha-hydroxylase (CYP7A1), the rate-limiting enzyme in the conversion of cholesterol to bile acids in the liver. In contrast to the liver-specific expression of CYP7A1, CYP7B1 mRNA transcripts were detected in human tissues involved in steroid genesis (brain, testes, ovary, and prostate) and in bile acid synthesis (liver) and reabsorption (colon, kidney, and small intestine). The human oxysterol 7alpha-hydroxylase transiently expressed in 293/T cells was able to catalyze 7alpha-hydroxylation of 27-hydroxycholesterol and dehydroepiandrosterone (DHEA). The human CYP7A1 and CYP7B1 both contain six exons and five introns. However, CYP7B1 spans at least 65 kb of the genome and is about 6-fold longer than CYP7A1. The transcription start site (+1) was localized 204 bp upstream of the initiation codon. No TATA box-like sequence was found near the transcription start site. Transient transfection assays of CYP7B1 promoter/luciferase reporter constructs in HepG2 cells revealed that the promoter was highly active. The 5' upstream region from nt -83 to +189 is the core promoter of the gene.

Animals↗
PubMed2002

Upstream AUGs modulate prion protein translation in vitro.

The level of expression of the host PrP gene (PRNP) has been shown to affect the progression to a disease, transmissible spongiform encephalopathy (TSE). In order to define sequences that are responsible for translation ofPRNPmRNA we have investigated a region comprising its 5'-leader sequence. Most remarkable, it consists of an almost identical Kozak mRNA sequence and two AUG initiation codons which seem to modulate translation of the prion protein mRNA in vitro. Although transcriptional regulation of the prion protein PRNP gene had been expected to dominate the translational modulation, our observations point to a translational regulation of the mouse prion protein synthesis controlled by ribosomal entry and usage of AUG codons.

5' Untranslated Regions↗
PubMed2003

[Sequence analyses of aberrant FHIT transcripts in gastric cancer cell lines].

BACKGROUND/AIMS: The fragile histidine triad (FHIT) gene located at chromosome 3p14.2, is a candidate tumor suppressor gene often involved in various tumors. Homozygous deletions, lack or reduced expression of FHIT protein, and alteration of its transcription were frequently observed in several types of primary human cancers and cell lines. In the present study, we examined the expression profiles of aberrant FHIT transcripts to explore the role of FHIT gene in gastric carcinogenesis. METHODS: In 6 gastric cancer cell lines, nested reverse transcription-polymerase chain reaction (RT-PCR) and cDNA sequence analyses were performed to detect and characterize the aberrant FHIT transcripts. RESULTS: In addition to the wild-type FHIT transcript, small-sized transcripts with various numbers and lengths were observed in all of the cell lines examined. cDNA sequence analysis confirmed that different types of truncated transcripts included exonic deletions, insertions of intron 5 sequences between exons, and combinations of both. Most of these transcripts lacked exon 5 in which translation initiation codon is located. Aberrant transcripts with partial exonic deletions due to activation of cryptic splice sites were also observed in 5 cell lines. Additionally, multi-step splice patterns indicative of additional downstream processing, were observed in several cancer lines. CONCLUSIONS: These results suggest that the aberrant FHIT transcripts in gastric cancer cell lines results from faulty splicing, including exon skipping, selection of cryptic splice site, and additional downstream splice processing.

Acid Anhydride Hydrolases↗
PubMed2004

Molecular basis of Diamond-Blackfan anemia: new findings from the Italian registry and a review of the literature.

BACKGROUND AND OBJECTIVES: Diamond-Blackfan anemia (DBA) is a rare, pure red blood cell aplasia of childhood caused by an intrinsic defect in erythropoietic progenitors. Malformations occur in about 40% of patients. More than half of patients respond to steroids; non-responders need chronic transfusions or stem cell transplantation (SCT). Mutations in the gene encoding ribosomal protein S19 are found in 25% of patients, but the link with erythropoiesis is unclear. A second DBA locus has been found on chromosome 8p22-p23; analysis of genes of the region is in progress. METHODS AND INFORMATION SOURCES: We present clinical and molecular data from 97 Italian DBA patients and a review of the literature. RESULTS AND STATE OF THE ART: We describe five new RPS19 gene mutations: four point mutations and one unbalanced chromosomal translocation. Hematologic findings, malformations and outcome are similar in the RPS19 mutated and the non-mutated groups. No genotype-phenotype correlation has been found so far in RPS19 mutated patients. Our data, however, and a thorough review of literature show a worse outcome (expressed as transfusion dependence) in patients with mutations that completely abolish one allele, i.e. gross chromosomal rearrangements and mutations at the initiation codon. The association of mental retardation with large deletions at the 19q locus points to a contiguous gene syndrome. A recurrent missense mutation (Arg62Trp) is associated with transfusion dependence in eight of the nine reported cases. PERSPECTIVES: Nationwide collaboration and population-based registries recording molecular data are essential for the further dissection of this rare heterogeneous disease and the definition of new therapeutic trials.

Anemia, Diamond-Blackfan↗
PubMed1990

The primary structure of the rat guanylyl cyclase A/atrial natriuretic peptide receptor gene.

We have isolated and characterized three genomic clones and a genomic fragment amplified by the polymerase chain reaction that contain the rat guanylyl cyclase-A (GC-A)/atrial natriuretic peptide receptor gene. The gene spans about 17.5 kilobases and includes 22 exons and 21 introns. All of the exon-intron junction sequences coincide with the GT/AG consensus. GC-A consists of at least the following four distinguishable domains: extracellular ligand binding, transmembrane, kinase-like, and cyclase catalytic. Exon 7 encodes the putative transmembrane domain. The kinase-like and catalytic domains are encoded by exons 8-15 and 16-22, respectively. The 5' end of the transcript, estimated by primer extension and S1 mapping, is 370 nucleotides upstream of the methionine initiation codon. The initiator sequence (-3 to +5) of CACACTCC has two mismatches when compared with a consensus initiator sequence of CTCANTCT. The 5'-flanking region contains three potential Sp1-binding sites and an inverted CCAAT box, but no apparent TATA box. Three different and short interspersed, repetitive sequences are found within intervening sequences and within the 5'- and 3'-flanking regions of the gene (five rat identifier, two rat type 2 Alu equivalent, and seven Alu-like sequences). They fall between the four major domains suggestive that these may be sites for frequent recombination events. This first reported structure of a gene for a member of this new enzyme/receptor family should facilitate the search for new family members, as well as allow studies to progress on the mechanisms by which the gene is regulated.

Amino Acid Sequence↗
PubMed1984

Yeast LEU2. Repression of mRNA levels by leucine and primary structure of the gene product.

It has been known that enzyme activity associated with the yeast LEU1 and LEU2 gene product (beta-isopropylmalate dehydrogenase) drops sharply when yeast is grown in the presence of leucine. RNA blot hybridizations with LEU2-specific probes establish that this is accompanied by a 5-fold repression in LEU2 mRNA levels. A similar repression was noted recently for LEU1 mRNA levels (Hsu, Y.-P., and Schimmel, P. (1984) J. Biol. Chem. 259, 3714-3719). Nuclease mapping of the 5'-end of the LEU2 mRNA shows a major start at approximately 16 nucleotides upstream of the AUG initiation codon. This initiation site in the gene is retained in an extensive LEU2 5'-noncoding region deletion which still expresses the LEU2 gene product (Erhart, E., and Hollenberg, C. P. (1983) J. Bacteriol. 156, 625-635). The primary structure of the LEU2 gene product was established from the nucleotide sequence of the gene-coding region and from fitting amino acid sequences of scattered internal peptides to the nucleotide sequence. The 364-amino acid protein has a 13-amino acid stretch which is highly homologous to the partially sequenced yeast LEU1 gene product (isopropylmalate isomerase). The homology occurs about 290 amino acids from the respective NH2 termini of the two proteins. The homology may represent residues which interact with beta-isopropylmalate, a common ligand for the enzymes.

3-Isopropylmalate Dehydrogenase↗
PubMed1996

Beta*, a UV-inducible smaller form of the beta subunit sliding clamp of DNA polymerase III of Escherichia coli. I. Gene expression and regulation.

The 40.6-kDa beta subunit of DNA polymerase III of Escherichia coli is a sliding DNA clamp responsible for tethering the polymerase to DNA and endowing it with high processivity (Stukenberg, P. T., Studwell-Vaughan, P. S., and O'Donnell, M. (1991) J. Biol. Chem. 266, 11328-11334). UV irradiation of E. coli induces a smaller 26-kDa form of the beta subunit, termed beta*, that, when overproduced from a plasmid, increases UV resistance of E. coli (Skaliter, R., Paz-Elizur, T., and Livneh, Z. (1996) J. Biol. Chem. 271, 2478-2481). Here we show that this protein is synthesized from a UV-inducible internal gene, termed dnaN*, that is located in-frame inside the coding region of dnaN, encoding the beta subunit. The initiation codon and the Shine-Dalgarno sequence of dnaN* were identified by site-directed mutagenesis. The dnaN* transcript was shown to be induced upon treatment with nalidixic acid, and transcriptional dnaN*-cat gene fusions were UV inducible, suggesting induction of dnaN* at the transcriptional level. Analysis of translational dnaN*-lacZ gene fusions revealed that UV induction was abolished in strains carrying the recA56, lexA3, or delta rpoH mutations, indicating involvement of both SOS and heat shock stress responses in the induction process. Expression of dnaN* represents a strategy of producing several proteins with related functional domains from a single gene.

Base Sequence↗
PubMed1995

Inhibition of influenza virus RNA polymerase and nucleoprotein of gene expression by antisense oligonucleotides.

We demonstrated that unmodified and modified (phosphorothioate) antisense oligonucleotides inhibit CAT (chloramphenicol acetyltransferase) protein expression in the clone 76 cell line. This cell line expresses the influenza virus RNA polymerase and nucleoprotein (NP) genes in response to dexamethasone. Antisense oligonucleotides with four target sites (PB1, PB2, PA, and NP) were synthesized and tested for the their inhibitory effects by a CAT-ELISA assay. Antisense phosphorothioate oligonucleotides (S-ODNs) complementary to the sites of the PB2-AUG and PA-AUG initiation codons showed a high inhibitory effect. On the other hand, the inhibitory effect of the S-ODNs targeted to PB1 was considerably decreased in comparison with the other three target sites.

Base Sequence↗
PubMed1996

Selection, identification, and genetic analysis of random mutants in the cloned primase/helicase gene of bacteriophage T7.

T7 gene 4 specifies two overlapping proteins 4A, a 566-amino acid primase/helicase, and 4B, a 503-amino acid helicase whose initiation codon is the 64th codon of the 4A protein. The 4A' gene, which has a leucine codon replacing the 4B initiation codon, specifies a single 566-amino acid protein that can provide the primase and helicase functions required for normal T7 growth. We selected N-methyl-N'-nitro-N-nitrosoguanidine mutants in the cloned 4A' gene that no longer support the growth of a phage that completely lacks gene 4. Genetic mapping of the 76 mutations found them to be distributed throughout the protein, including both the N-terminal and C-terminal halves of the molecule thought to represent primase and helicase domains, respectively. Complementation tests with partially and completely defective phage showed that all but five of the mutants lacked helicase function but retained primase function. The other five, which lacked both functions, all made short proteins, including one missing only 60 amino acids. No mutations lacked only primase function, and none mapped within the first 105 amino acids, which includes the 63-amino acid region unique to 4A that contains elements required to recognize primase sites. Forty-six mutations were sequenced and included 27 missense mutations affecting 25 amino acids. Many mutations in the N-terminal half of the protein affected its solubility in cell extracts. Mutations in the C-terminal half clustered in or near five helicase consensus sequences. Biochemical analysis of nine of the mutant proteins is described in the accompanying paper (Washington, M. T., Rosenberg, A. H., Griffin, K., Studier, F. W., and Patel, S. S. (1996) J. Biol. Chem. 271, 26825-26834).

Amino Acid Sequence↗
PubMed1998

Identification of alternatively spliced transcripts encoding murine macrophage colony-stimulating factor.

We have isolated a novel cDNA encoding macrophage colony-stimulating factor (M-CSF) from a murine stromal cell line, ST2. The cDNA included an entire coding sequence of the M-CSF gene but contained an additional sequence of 140 base pairs (bp). Northern blot analysis demonstrated that other murine cell lines such as a fibroblastic cell line (L) and a stromal cell line (PA6) also expressed the transcripts corresponding to the clone. The nucleotide sequence analyses of the cDNA and the cloned M-CSF genome revealed that the 140-bp insertion sequence was part of intron 1 which separated exon 1 and exon 2: the former contained part of the amino acid residues of the signal sequence and the latter the rest of the signal sequence and the first 22 amino acid residues of the mature protein. The insertion of the 140-bp intron sequence not only changed the amino acid sequence of the signal peptide but also generated an in-frame termination codon. However, instead of the dysfunction of the original initiation codon, the 140-bp insertion sequence contained a putative ATG initiation codon that preserved the original open reading frame. Finally, we found that the cDNA directed the expression of a secreted and biologically active M-CSF protein when it was introduced into COS7 cells and M-CSF activity in the culture supernatants was measured using an M-CSF-dependent cell line. These results indicate the presence of an alternatively spliced M-CSF transcript which utilizes an alternate initiation codon in order to specify active M-CSF protein.

Alternative Splicing↗
PubMed2004

Differential utilization of upstream AUGs in the beta-secretase mRNA suggests that a shunting mechanism regulates translation.

beta-Secretase [also known as the beta-site amyloid precursor protein-cleaving enzyme 1 (BACE1)] is an enzyme involved in the production of A beta-amyloid plaques in the brains of patients with Alzheimer's disease. The enhanced production of this enzyme occurs without corresponding changes in BACE1 mRNA levels. The complex 5' leader of BACE1 mRNA contains three upstream ORFs (uORFs) preceding the BACE1 initiation codon. In this study, we investigated how this 5' leader affects translation efficiency as a first step in understanding the enhanced production of the enzyme in the disease. Using reporter constructs in transfected mammalian cell lines and cell-free lysates, we showed that the translation mediated by the BACE1 5' leader is cap-dependent and inhibited by cis-acting segments contained within the 5' leader. Disruption of the uORFs had no effect on translation in B104 cells, which was surprising because the first two AUGs reside in contexts able to function as initiation codons. Possible mechanisms to explain how ribosomes bypass the uORFs, including reinitiation, leaky scanning, and internal initiation of translation were found to be inconsistent with the data. The data are most consistent with a model in which ribosomes shunt uORF-containing segments of the 5' leader as the ribosomes move from the 5' end of the mRNA to the initiation codon. In PC12 cells, however, the second uORF appears to be translated. We hypothesize that the translation efficiency of the BACE1 initiation codon may be increased in patients with Alzheimer's disease by molecular mechanisms that enhance shunting or increase the relative accessibility the BACE1 initiation codon.

Amyloid Precursor Protein Secretases↗
PubMedDate not supplied

Structure of the PCCA gene and distribution of mutations causing propionic acidemia.

Propionyl-CoA carboxylase (PCC, EC 6.4.1.3) is a mitochondrial, biotin-dependent enzyme that functions in the catabolism of branched-chain amino acids, fatty acids with odd-numbered chain lengths, and other metabolites. It catalyzes the ATP-dependent carboxylation of propionyl-CoA to d-methylmalonyl-CoA. PCC is composed of two types of subunits, likely as alpha4beta4 or alpha6beta6, with the alpha subunit containing the covalently bound biotin prosthetic group. A genetic deficiency of PCC activity causes propionic acidemia, a potentially fatal disease with onset in severe cases in the newborn period. Affected patients may have mutations of either the PCCA or PCCB gene. In this study, we have determined the structure of the human PCCA gene which, at the present time, is only partially represented in the databases. Based on reported ESTs and confirmed by RT-PCR, we also redefine the translation initiation codon to a position 75 nucleotides upstream of the currently accepted initiation codon. We show the distribution of mutations, including three identified in this study, and renumber all reported mutations to count from the new initiation codon. The gene spans more than 360 kb and consists of 24 exons ranging from 37 to 335 bp in length. The introns range in size from 104.bp to 66 kb. We have also determined the nucleotide sequence of approximately 1 kb of the 5'-flanking region upstream of the ATG translation initiation site. The proximal 400 bp of the 5'-flanking region shows a high G + C content (67%) and is part of a putative 1-kb CpG island that extends into exon 1 and part of intron 1. The putative promoter lacks a TATA box but contains two AP-1 sites and a conservatively defined consensus GC box, the latter characteristic of the core binding sequence of the Sp1 transcription factor.

Alternative Splicing↗
PubMed2000

Expression of mitochondrial protein-coding genes in Tetrahymena pyriformis.

In the ciliate protozoon, Tetrahymena pyriformis, mitochondrial protein-coding genes are highly divergent in sequence, and in a number of cases they lack AUG initiation codons. We asked whether RNA editing might be acting to generate protein sequences that are more conventional than those inferred from the corresponding gene sequences, and/or to create standard AUG initiation codons where these are absent. However, comparison of genomic and cDNA sequences (the latter generated by reverse transcriptase sequencing of T. pyriformis mitochondrial mRNAs) yielded no evidence of mitochondrial RNA editing in this organism. To delineate the 5' ends of mitochondrial protein-coding transcripts, primer extension experiments were conducted. In all cases, 5' termini were found to map within a few nucleotides of potential initiation codons, indicating that T. pyriformis mitochondrial mRNAs have little or no 5' untranslated leader sequence. The pattern of strong primer extension stops suggested that both standard (AUG) and non-standard (AUU, AUA, GUG, UUG) initiation codons are utilized by the Tetrahymena mitochondrial translation system. We also investigated expression of the nad1 gene, which in both T. pyriformis and Paramecium aurelia is split into two portions that are encoded by and transcribed from different DNA strands. Northern hybridization analysis showed that the corresponding transcripts are not trans-spliced, implying that separate N-terminal and C-terminal portions of Nad1 are made in this system. Finally, in a search for primary transcripts, we isolated from a T. pyriformis mitochondrial fraction several small RNAs that were reproducibly labeled by incubation in the presence of [alpha-(32)P]GTP and guanylyltransferase. Partial sequence information revealed that none of these cappable RNAs is encoded in the T. pyriformis mitochondrial genome.

5' Untranslated Regions↗
PubMed1995

Quantification analysis of translation initiation signal sequences in vertebrate mRNAs.

The signal for directing the position of translation initiation in vertebrate mRNAs requires not only ATG initiation codon but also sequences flanking the initiation codon. A consensus sequence, (GCC) GCC (A or G) CCATGG has been proposed for the signal, but actual initiation sequences differ from it in a greater or lesser degree. In the present report, the translation initiation signal sequences of rat preproinsulin mRNA and its mutant mRNAs were analyzed using a quantification method, which demonstrates that strength of the signal plays important role in determining efficiency of initiation reaction.

Animals↗
PubMed2004

Heterogeneous nuclear ribonucleoprotein A1 is a novel internal ribosome entry site trans-acting factor that modulates alternative initiation of translation of the fibroblast growth factor 2 mRNA.

Alternative initiation of translation of the human fibroblast growth factor 2 (FGF-2) mRNA at five in-frame CUG or AUG translation initiation codons requires various RNA cis-acting elements, including an internal ribosome entry site (IRES). Here we describe the purification of a trans-acting factor controlling FGF-2 mRNA translation achieved by several biochemical purification approaches. We have identified the heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) as a factor that binds to the FGF-2 5'-leader RNA and that also complements defective FGF-2 translation in vitro in rabbit reticulocyte lysate. Recombinant hnRNP A1 stimulates in vitro translation at the four IRES-dependent initiation codons but has no effect on the cap-dependent initiation codon. Consistent with a role of hnRNP A1 in the control of alternative initiation of translation, short interfering RNA-mediated knock down of hnRNP A1 specifically inhibits translation at the four IRES-dependent initiation codons. Furthermore, hnRNP A1 binds to the FGF-2 IRES, implicating this interaction in the control of alternative initiation of translation.

5' Untranslated Regions↗
PubMed1995

Translation initiation and assembly of peripherin in cultured cells.

The peripherin gene has three potential ATG translation initiation sites at positions 38, 56, and 290. The second ATG has been proposed to be the initiation codon used for translation of the protein, but there is no experimental evidence for this conjecture. We have isolated a full-length peripherin cDNA (designated as p61-11) from a rat brain cDNA library. Upon sequencing, we found that this cDNA contains a point mutation at the second potential translation initiation codon, which changes this ATG to ACG. When expressed in SW13 cl.2 vim- cells, a cell line without any detectable cytoplasmic intermediate filaments, the protein product of p61-11 cannot form a filamentous network and the major product is 45 kDa in size, which is most likely initiated from the third ATG. The protein product from the first ATG (57 kDa in size) of p61-11 is also detected albeit in smaller amounts. We introduced a frame-shift mutation upstream of the third ATG in p61-11 to create p61-11FS and showed that the third ATG is able to initiate translation efficiently even in the presence of the first ATG, and the 45 kDa protein leads to a diffuse nonfilamentous staining pattern in vim- cells confirming that the first ATG may not be the preferred translation initiation codon, since it cannot suppress a downstream ATG. We increased the translation efficiency from the first ATG of p61-11 by mutating the three nucleotides preceding this first ATG and thereby placing it in a better Kozak consensus sequence for translation initiation. The resulting 57 kDa protein is able to form a filamentous network in vim- cells. We corrected the mutation in the original p61-11 by polymerase chain reaction and generated two peripherin constructs: perM1M2 (which contains all three translation initiation codons) and per delta 1M2 (the first ATG is deleted, but the other two are present). When transfected, their protein products, about 57 kDa in size, form filamentous networks in the absence of other cytoplasmic intermediate filaments. Since there is no 45 kDa protein detected for these latter two constructs, it is reasonable to conclude that in the presence of the second ATG, little or no translation is initiated from the third ATG. Taken together, these results strongly suggest that the second ATG is the preferred translation initiation codon for the peripherin gene.

Adenocarcinoma↗