Biomedical subjects

Chaoneng Ji

Publications and source records attributed to Chaoneng Ji.

72 records · Page 4Linked to original sources

PubMed2003

Isolation and characterization of a human putative receptor protein kinase cDNA STYK1.

Protein kinases (PKs) represent a well studied but most diverse protein superfamily. The covalent, reversible linkage of phosphate to serine, threonine, and tyrosine residues of substrate proteins by protein kinases is probably ubiquitous cellular mechanism for regulation of physiological processes. It is known to us that most signaling pathways impinge at some point on protein kinases. Here we report a human putative receptor protein kinase cDNA STYK1. The STYK1 cDNA is 2749 base pairs in length and contains an open reading frame encoding 422 amino acids. The STYK1 gene is mapped to human chromosome 12p13 and 11 exons were found. RT-PCR showed that STYK1 is widely expressed in human tissues.

Amino Acid Sequence↗

PubMed2003

Cloning and sequence analysis of the human cDNA encoding the synaptoporin (delta), a highly conservative synaptic vesicle protein.

Synaptoporin is a membrane protein of synaptic vesicles, which belongs to the synaptophysin family. It was first isolated from rat brain. Here we report the cloning and characterization of the human cDNA that encodes the human homologue of synaptoporin. It has two splicing variants, which is in accordance with its ortholog in chicken. Its deduced amino acid sequence displays 97% and 81% identity with the synaptoporin of rat and chicken, respectively. This gene was mapped to the chromosome 3p14.3 by matching against the Human Genome Sequence Database. 16-tissue RT-PCR analysis shows that human synaptoporin is specifically expressed in the brain.

Amino Acid Sequence↗

PubMed2003

Cloning and characterization of the human IFT20 gene.

Intraflagellar transport (IFT), in which molecular motors and IFT particle proteins participate, is very important in assembling and maintaining many cilia/flagella, such as the motile cilia that drive the swimming of cells and embryos, the nodal cilia that generate left-right asymmetry in vertebrate embryos, and the sensory cilia that detect sensory stimuli in some animals. Here we report the molecular cloning and characterization of a novel human cDNA that is 1060 base pair in length, encoding a putative protein of 158 amino acid residues which shares high homology to Mus musculus intraflagellar transport protein mIFT20 (Accession number AAL99202, identity 82.3%, similarity 82.9%) at protein level. Bioinformatics analysis revealed that the gene is composed of 6 exons and is located on human chromosome 17p 11.1. RT-PCR showed that this gene is expressed in human brain, lung, kidney and pancreas, and lower expression were also detected in human placenta, liver, thymus, prostate and testis.

Amino Acid Sequence↗

PubMed2003

Characterization of a novel splicing variant of KLHL5, a member of the kelch protein family.

The kelch-repeat protein family is a recently found new kind of actin-binding protein. It is characterized by tandemly arranged motifs of about 50 amino acids. Previous study showed that most members of the kelch-repeat family were cytoskeletal proteins implicated in various cellular processes, such as actin cytoskeleton interaction, cytoplasmic sequestration of transcription factors and cell morphology. And some of the family members play important roles in tissue development, such as human ENC-1, NRP/B, etc. Another characteristic of the kelch family is that most members have another conserved BTB domain at the extreme amino terminus. The BTB domain is also found at the N-terminus of 5-10% of zinc-finger transcription factor types and is a conserved protein-protein interaction motif. During the large-scale sequencing analysis of a human fetal brain cDNA library we found a novel kelch-like protein gene 5, KLHL5, KLHL5 has high identity with Drosophila kelch protein and many other family members. Here we report a novel splicing variants of KLHL5, named KLHL5b and the expression pattern of KLHL5b in many tissues.

Alternative Splicing↗

PubMed2003

Molecular cloning and characterization of a novel human putative transmembrane protein homologous to mouse sideroflexin associated with sideroblastic anemia.

Sideroflexin1 (Sfxn1), the prototype of a novel family of evolutionarily conserved proteins present in eukaryotes, has been found mutated in mice with siderocytic anemia. It is speculated that this protein facilitates the transport of a component required for iron utilization into mitochondrial. During the large-scale sequencing analysis of a human fetal brain cDNA library, we isolated a cDNA encoding a novel sideroflexin protein (SFXN4), which showed 59% identity and 71% similarity to mouse sideroflexin4. According to the search of the human genome database, SFXN4 gene is mapped to chromosome 10q25-26 and spans more than 24.7kb of the genomic DNA. It is 1428 base pair in length and the putative protein contains 305 amino acids with a conserved predicted five-transmembrane-domains structure. RT-PCR result shows that the SFXN4 gene is expressed in many tissues.

Amino Acid Sequence↗

PubMed2003

Cloning and characterization of a novel splice variant of the brain-specific protein densin-180.

Densin-180 is a brain-specific synaptic protein of the o-sialoglycoprotein family. It functions in specific adhesion between presynaptic and postsynaptic membranes at glutamatergic synapses. We have cloned a novel splice variant of densin-180 from a fetal brain cDNA library and termed it LRRC7. It is located on 1p31 and consists of 8 exons. It encodes a putative protein of 216 amino acids which contains a nuclear localization signal and four leucine-rich repeats (LRRs). LRRs are 20-29 residue sequence motifs present in a number of proteins with diverse functions. Expression analysis of LRRC7 shows it is expressed ubiquitously while its splice variant densin-180 is brain-specific.

Alternative Splicing↗

PubMed2003

Identification and expression analysis of a novel splice variant of human Sprouty1 gene.

Sprouty (SPRY) was first identified in a genetic screen in Drosophila to be an antagonist of fibroblast growth factor (FGF) and epidermal growth factor (EGF) signaling, seemingly by inhibiting the Ras/MAP kinase pathway. During large scale DNA sequencing of the human fetal brain cDNA library, we cloned a novel splice variant of human Sprouty1 gene, and termed it human Sprouty1b (SPRY1b). It has the same deduced protein as Sprouty1a, which has been reported. And like other members of Sprouty family, SPRY1b deduced protein also has a C-terminal cysteine-rich region. According to the search against human genome database, SPRY1b was mapped to 4q25-28. Expression analysis of SPRY1a and SPRY1b shows that they are hardly expressed in adult human, but have different expression patterns in fetus, which confirmed that SPRY1 is an important gene during fetal development.

Adaptor Proteins, Signal Transducing↗

PubMed2003

A novel splice variant of human gene GDPD1 is mainly expressed in human ovary and small intestine.

Glycerophosphodiester phosphodiesterase (GDPD) is a glycerol metabolizing enzyme that has been previously identified in Escherichia coli, Haemophilus influenzae, Bacillus subtilis and Borrelia hermsii. It has been also reported that there is putative protein containing GDPD domain in Mus musculus, but not in Homo sapiens. SMART analysis showed that our predicted protein and three others of the same gene also comprise this domain. Because the gene has not been named, we termed it GDPD1 and accordingly termed our splice variant GDPD1_v1 after acquiring the agreement of HUGO. RT-PCR experiment revealed that our splice variant of the gene is mainly expressed in human ovary and small intestine, basically conforming to the result of serial analysis of gene expression.

Alternative Splicing↗

PubMed2002

cDNA cloning and expression analysis of a novel human F-box only protein.

F-box proteins are an expanding family of eukaryotic proteins that are characterized by an approximately 40 amino acid motif. Some F-box proteins are critical for the controlled degradation of cellular regulatory proteins. During a large-scale sequencing analysis of a human fetal brain cDNA library, we isolated a cDNA clone that encodes a novel F-box protein. It showed a 90.0% identity with the previously isolated mouse F-box protein16 at the amino acid level. Northern blot analysis showed no detectable expression, while reverse transcription-polymerase chain reaction analysis indicated that FBXO16 was expressed in the heart, spleen, and colon. By mapping, we localized the FBXO16 gene to the human chromosome 8p12. The FBXO16 gene consisted of 9 exons that spanned 67,816 bp of human genomic DNA.

Amino Acid Sequence↗

PubMed2002

Molecular cloning and characterization of a novel human cAMP response element-binding ( CREB) gene ( CREB4).

Cyclic adenosine monophosphate (cAMP) response element-binding (CREB) proteins are a family of mammalian transcription activators. We identified a novel human CREB gene ( CREB4) that was 1592 bp long and encoded a protein of 395 amino acid residues. The protein shared high homology to mouse CREB3 (identity 62%, similarity 72%). The expression pattern of the human CREB4 gene showed transcripts in prostate, brain, pancreas, skeletal muscle, small intestine, testis, leukocyte, and thymus, whereas in heart, lung, liver, kidney, placenta, spleen, ovary, and colon, specific bands of the transcript could not be detected. The CREB4 gene consisted of ten exons and nine introns and was mapped to chromosome 1q21.3 by means of a bioinformatics analysis.

Amino Acid Sequence↗

PubMed2002

A novel splice variant of the cell adhesion molecule contactin 4 ( CNTN4) is mainly expressed in human brain.

Axon-associated cell adhesion molecules (AxCAMs) of the immunoglobulin superfamily play important roles in the formation, maintenance, and plasticity of functional neuronal networks. Contactin4 ( CNTN4, BIG-2) is a member of the TAG-1/F3 subgroup of AxCAMs. We have cloned a novel splice variant of CNTN4, and term it CNTN4A. The complete nucleotide sequence of CNTN4 is also obtained by combining the insert sequences of two clones, which were isolated when screening the human fetal brain cDNA library with CNTN4A as a probe. CNTN4A protein has an N-terminal cleavable signal peptide, two FNIII-like domains, and a glycosyl phosphatidylinositol-anchoring domain. According to the search of the human genome database, CNTN4 was mapped to 3p25-26, a region very close to the breakpoints of the 3p syndrome. Expression analysis of CNTN4A shows that CNTN4A is mainly expressed in brain.

Alternative Splicing↗

PubMed2002

Molecular cloning and characterization of a novel human Rab ( Rab2B) gene.

Rab proteins are small-molecular-weight guanosine triphosphatases (GTPases) that control vesicular traffic in eukaryotic cells. The small GTPase Rab2 is a resident of pre-Golgi intermediates and is required for protein transport from the endoplasmic reticulum to the Golgi complex. We identified a novel human Rab (Rab2B) gene that was 2312 bp in length and encoded a protein of 216 amino acid residues. The protein shared high homology with mouse Rab2 (identity 83%, similarity 91%). The expression pattern of the human Rab2B gene showed that there is a transcript in kidney, prostate, lung, liver, thymus, colon, pancreas, and skeletal muscle, and low levels in placenta, whereas specific bands of the transcript could not be detected in heart, brain, spleen, testis, ovary, small intestine, and leukocyte. Overexpression has been observed in colon adenocarcinoma CX-1. The Rab2B gene consists of nine exons and eight introns and is mapped to chromosome 14q11.1-14q11.2 by bioinformatics analysis.

Aged↗

PubMed2002

NADPH-dependent GMP reductase isoenzyme of human (GMPR2). Expression, purification, and kinetic properties.

GMP reductase (EC 1.6.6.8) is the only known metabolic step by which guanine nucleotides can be converted to the pivotal precursor of both adenine and guanine nucleotides. Human GMP reductase has been previously partially purified from erythrocytes and a chromosome 6-linked cDNA has been identified to correspond for encoding human GMP reductase. Here, we reported a distinct cDNA for human GMP reductase isoenzyme isolated from a human fetal brain library, and the GenBank accession number is AF419346. The deduced protein shows 90% identity with human GMP reductase reported (named GMPR1 compared with GMPR2 of this paper) and 69% with E. coli GMP reductase. Comparison of GMPR2 cDNA sequence with human genome indicates the corresponding gene spans about 6.6kb on chromosome 14, which encodes 348 amino acid residues. Northern hybridization analysis indicates a differential and disproportionate expression of mRNAs for GMPR1 and GMPR2, suggesting the existence of distinct molecular species of GMP reductase in human. The apparent Km of GMPR2 for NADPH and GMP are 26.6 and 17.4 microM, respectively. This is the first report suggesting the existence of two distinct types of human GMP reductase molecular species, which can be used to explain the bimodal saturation curve noted with the purified human erythrocyte GMP reductase.

Amino Acid Sequence↗

PubMed2002

Cloning, expression and characterization of a novel human VMP gene.

We report here cloning and characterization of a novel human gene, termed VMP, which is a vesicular membrane protein. RT-PCR analysis shows that VMP is expressed exclusively in brain of the 16 tissues examined, suggesting that it is a neuron-specific membrane protein. The cDNA encodes 195 amino acid with a putative molecular weight of about 24 KDa. VMP contains two putative membrane spanning domains and a hydrophilic tail homologous to the microtubule-binding domain of MAPs. So it is speculated that VMP may associated with microtubules through its C-terminal and plays an important role in vesicular organelles transport and nerve signals.

Base Sequence↗

PubMed2002

Cloning and characterization of a novel human STAR domain containing cDNA KHDRBS2.

KHDRBS2, KH domain containing, RNA binding, signal transduction associated 2, is an RNA-binding protein that is tyrosine phosphorylated by Src during mitosis. It contains a KH domain,which is embedded in a larger conserved domain called the STAR domain. This protein has a 99% sequence identity with rat SLM-1 (the Sam68-like mammalian protein 1) and 98% sequence identity with mouse SLM-1 in its STAR domain. KHDRBS2 has the characteristic Sam68 SH2 and SH3 domain binding sites. RT-PCR analysis showed its transcript is ubiquitously expressed. The characterization of KHDRBS2 indicates it may link tyrosine kinase signaling cascades with some aspect of RNA metabolism.

Amino Acid Sequence↗

PubMed2002

Cloning and characterization of a novel human alcohol dehydrogenase gene (ADHFe1).

There are three types of NAD(P)(+)-dependent alcohol dehydrogenase: "medium-chain" zinc-containing enzymes, "short-chain" zinc-lacking enzymes and iron-activated enzymes. Although the medium-chain family and the short-chain family have been characterized in human, the iron-activated alcohol dehydrogenase family seems to exist only in microbial organisms. We have now cloned and characterized an iron-activated alcohol dehydrogenase gene, Fe-containing alcohol dehydrogenase 1 (ADHFe1) in human. The cDNA was isolated from the human fetal brain cDNA library. It contains a long open reading frame, which is not homologous with the other alcohol dehydrogenases isoenzymes characterized in human. The hypothetical alcohol dehydrogenase does, however, show strong homology to the iron-activated alcohol dehydrogenases from microbial organisms. Northern blotting analysis only detected expression in adult liver tissue. At least two different splicing variants were screened by PCR using the multiple tissue cDNA panels as templates.

Alcohol Dehydrogenase↗

PubMed2002

Molecular cloning, mapping and characterization of a human CK1gamma1 gene.

We isolated and sequenced a cDNA clone coding a human protein kinase CK1 (casein kinase 1) by screening a human fetal brain cDNA library. This new cDNA clone of 1756 bp contained an open reading frame, encoding a protein of 438 amino acids with a molecular weight of 50,272 Da and an isoelectric point of 9.37. The entire amino acid sequence of the novel human CK1 was 94% homologous to that of rat CK1gamma1. Northern blot analysis indicated that the human CK1gamma1 was highly expressed in the liver, skeletal muscle, heart and kidney. Furthermore, the human CK1gamma1 gene was mapped to chromosome 15q22 between STS marker D15S159 and D15S125 by polymerase chain reaction analysis of human/rodent hybrid cell panels.

Amino Acid Motifs↗

PubMedDate not supplied

Molecular cloning and characterization of a novel human kinase gene, PDIK1L.

We isolated a 4301-bp cDNA from a human foetal brain cDNA library by high-throughput cDNA sequencing. It encodes a protein of 341 amino acids, which shows 69% identity with the human kinase CLIK1 (AAL99353), which was suggested to be the CLP-36 interacting kinase. Bioinformatics analysis suggests that the putative kinase may interact with PDZ and LIM domain proteins. Therefore the protein and its cDNA were named 'PDLIM1 interacting kinase 1 like' (PDIK1L; nomenclature approved by the HUGO Gene Nomenclature Committee). Ensembl Genome Browser located PDIK1L to human chromosome 1p35.3. It spans about 13.7 kb and consists of four exons and three introns. Multiple-tissue cDNA panel PCR revealed that the gene is expressed widely in human tissues: liver, kidney, pancreas, spleen, thymus and prostate. The protein appears to be localized to the nucleus.

Amino Acid Sequence↗