Isolation and oncogenic potential of a novel human src-like gene.

We have isolated cDNA molecules representing the complete coding sequence of a new human gene which is a member of the src family of oncogenes. Nucleotide sequence analysis revealed that this gene, termed slk, encoded a 537-residue protein which was 86% identical to the chicken proto-oncogene product, p60c-src, over a stretch of 191 amino acids at its carboxy terminus. In contrast, only 6% amino acid homology was observed within the amino-terminal 82 amino acid residues of these two proteins. It was possible to activate slk as a transforming gene by substituting approximately two-thirds of the slk coding sequence for an analogous region of the v-fgr onc gene present in Gardner-Rasheed feline sarcoma virus. The resulting hybrid protein molecule expressed in transformed cells demonstrated protein kinase activity with specificity for tyrosine residues.     

大鼠脑红蛋白基因编码区的克隆、多态性分析及该基因组织表达谱研究

参考人和小鼠脑红蛋白（Neuroglobin,NGB)的cDNA序列设计简并引物,用RT－PCR方法从大鼠脑组织中扩增出大鼠NGB基因编码区的cDNA序列,该序列与小鼠NGB基因编码区的序列同尖性为96％,与人NGB基因编码区的序列同源性为88％,进一步分析表明,大鼠NGB基因编码区存在多个多态性位点;113t/c[138P],133a/g[N45D],388a/g[R130G],417t/c.该序列已被GenBank接受,登录号为AF333245,RT－PCR分析表明,该基因在大鼠脑,肝,肾,心肌和骨骼肌中均有较高水平表达,提示了其功能上的重要性。     

Molecular cloning and characterization of a chromosomal gene for human eosinophil peroxidase

Using human myeloperoxidase cDNA as a probe, a chromosomal gene related to myeloperoxidase was isolated from a human gene library. Comparison of the amino acid sequence deduced from the nucleotide sequence of the cloned gene with that of human eosinophil peroxidase purified from buffy coats has indicated that the isolated gene is the chromosomal gene for human eosinophil peroxidase. Like human myeloperoxidase gene, human eosinophil peroxidase gene consists of 12 exons and 11 introns spanning about 12 kilobases. The gene can code for a protein of 715 amino acids with a calculated Mr of 81,036. The heavy chain and the light chain of eosinophil peroxidase were located on the COOH and NH2 terminus of the protein, respectively. The coding sequences of eosinophil peroxidase and myeloperoxidase show homologies of 72.4% at the nucleotide and 69.8% at the amino acid level, while little homology was found in the 5'-flanking region. Northern hybridization and S1 mapping analysis of RNA from human leukemic cells have indicated that the eosinophil peroxidase gene is expressed in the eosinophilic subline of human HL-60 cells but not in the neutrophilic subline or in parental HL-60 cells.     

Sequence analysis of the large and small subunits of human ribonucleotide reductase.

We have isolated and sequenced overlapping cDNA clones from a breast carcinoma cDNA library containing the entire coding region of both the R1 and R2 subunits of the human ribonucleotide reductase gene. The coding region of the human R1 subunit comprises 2376 nucleotides and predicts a polypeptide of 792 amino acids (calculated molecular mass 90,081). The sequence of this subunit is almost identical to the equivalent mouse ribonucleotide reductase subunit with 97.7% homology between the mouse and human R1 subunit amino acid sequences. The coding region of the human R2 subunit of ribonucleotide reductase comprises 1170 nucleotides and predicts a polypeptide of 389 amino acids (calculated molecular mass 44,883), which is one amino acid shorter than the equivalent mouse subunit. The human and mouse R2 subunits display considerable homology in their carboxy-terminal amino acid sequences, with 96.3% homology downstream of amino acid 68 of the human and mouse R2 proteins. However, the amino-terminal portions of these two proteins are more divergent in sequence, with only 69.2% homology in the first 68 amino acids.     

Structure and sequence of the human homeobox gene HOX7.

A cosmid containing the human sequence HOX7, homologous to the murine Hox-7 gene, was isolated from a genomic library, and the positions of the coding sequences were determined by hybridization. DNA sequence analysis demonstrated two exons that code for a homeodomain-containing protein of 297 amino acids. The open reading frame is interrupted by a single intron of approximately 1.6 kb, the splice donor and acceptor sites of which conform to known consensus sequences. The human HOX7 coding sequence has a very high degree of identity with the murine Hox-7 cDNA. Within the homeobox, the two sequences share 94% identity at the DNA level, all substitutions being silent. This high level of sequence similarity is not confined to the homeodomain; overall the human and murine HOX7 gene products show 80% identity at the amino acid level. Both the 5' and 3' untranslated regions also show significant similarity to the murine gene, with 79 and 70% sequence identity, respectively. The sequence upstream of the coding sequence of exon 1 contains a GC-rich putative promoter region. There is no TATA box, but a CCAAT and numerous GC boxes are present. The region encompassing the promoter region, exon 1, and the 5' region of exon 2 have a higher than expected frequency of CpG dinucleotides; numerous sites for rare-cutter restriction enzymes are present, a characteristic of HTF islands.     

一条大鼠睾丸新基因的生物信息学分析及真核表达

目的：探讨大鼠睾丸组织一条新基因的生物信息学特征和真核表达。方法：构建pEGFP-N1载体的融合质粒进行真核表达,利用生物信息学手段分析基因和蛋白功能。结果：生物信息学分析表明RSA14-44的编码区序列与人类及鼠源RAS同源基因家族核酸序列达到85%以上的同源性;RSA14-44蛋白没有典型的跨膜结构域,也没有典型的N末端信号肽;与人类RhoA蛋白序列达到了89%的同源且具有Rho家族成员的GAAX盒和p-loop结构的基序特征;RSA14-44蛋白大部分氨基酸序列与Rho家族7个已知结构域高度同源;RSA14-44基因真核表达定位于细胞质。结论：RSA14-44基因真核表达定位于CHO-K1细胞质,;编码蛋白质与Rho家族同源性高,为进一步研究其生物学功能提供参考。     

Cloning, expression, and sequence homologies of cDNA for human carbonic anhydrase II

A cDNA clone for human carbonic anhydrase (CA) II was isolated from a kidney lambda gt10 library. Expression of the cDNA insert in Cos-7 cells produced an immunoprecipitable product and enzymatically active carbonic anhydrase. The cDNA insert is 1551 bp in length and contains an open reading frame which encodes a 260-amino-acid polypeptide. The deduced amino acid sequence is identical to that reported for human CA II. The protein coding region of this cDNA for human CA II shows 81 and 70% nucleotide identity with cDNAs for CA II from mouse and chick, respectively. Even the long 3'-untranslated region of the cDNA for human CA II (703 bp) is 64 and 42% identical to those of CA II from mouse and chick, showing remarkable conservation of the CA II cDNAs in amniotes. The protein coding region of the human CA II cDNA is 64 and 65% identical with those of human CA I and CA III, which are thought to have arisen from a common precursor by gene duplication.     

Nucleotide sequence analysis identifies the human c-sis proto-oncogene as a structural gene for platelet-derived growth factor

The simian sarcoma virus transforming gene, v-sis, encodes a protein, p28sis , that is closely related to human platelet-derived growth factor (PDGF). The human locus related to v-sis was cloned and shown to contain at least five exons corresponding to the v-sis coding region. Nucleotide sequence analysis of these exons revealed that the predicted amino acid sequence of human c-sis differed by 6% from that of the woolly monkey-derived v-sis. These findings imply that the sis proto-oncogene has been well conserved during primate evolution. By comparison of the known amino acid sequences of PDGF peptides with the predicted human c-sis protein, it was possible to demonstrate that this human proto-oncogene is the structural gene encoding one of the two major polypeptides of this potent mitogen for connective tissue cells.     

Human GAP-43: its deduced amino acid sequence and chromosomal localization in mouse and human

The growth-associated protein (GAP-43) is considered a crucial component of an effective regenerative response in the nervous system. Its phosphorylation by protein kinase C correlates with long-term potentiation. Sequence analysis of human cDNAs coding for this protein shows that the human GAP-43 gene is highly homologous to the rat gene; this homology extends into the 3'-untranslated region. However, the human protein contains a 10 amino acid insert. Somatic cell hybrids demonstrate localization of the GAP-43 gene to human chromosome 3 and to mouse chromosome 16.     

Structure, evolution, and tissue-specific synthesis of human apolipoprotein AIV

Apolipoprotein AIV (apoAIV) is a protein of the lipid transport system found associated with chylomicrons, high-density lipoprotein (HDL), and the lipoprotein-free fraction of the plasma. The gene coding for the human apoAIV is closely linked with the genes coding for apolipoproteins AI (apoAI) and CIII (apoCIII). In this paper a nearly full-length apoAIV cDNA clone has been isolated by screening an adult human liver DNA library using a human apoAIV gene probe. In-frame translation of the cDNA sequence in this clone indicated that the human apoAIV consists of 396 amino acid residues including a 20 residue long signal peptide. The coding region of this cDNA sequence contains 15 nucleotide repeats, 11 of which code for amino acid repeats with potentials of forming amphipathic helices. Alignment and comparison of the human and rat apoAIV amino acid sequences indicated a five-residue deletion near the carboxy terminus of the rat protein. This comparison also indicated that these proteins are 61.8% homologous, suggesting that the rate of evolution of apoAIV is 65 accepted point mutations (PAMs) per 100 residues per 100 million years. The rates of evolution of certain amino acid repeats in apoAIV are higher than the rate of evolution of the entire protein. However, the corresponding, computer-generated, secondary structures and hydropathy profiles of these repeats are very similar between the human and rat apoAIV. The relative steady-state levels of apoAIV mRNA in various human and monkey tissues were determined by hybridization blotting analysis of total RNA from these tissues using a human apoAIV cDNA probe.(ABSTRACT TRUNCATED AT 250 WORDS)