Yuan Jiangang

Cloning and prokaryotic expression of HGLP cDNA

A novel cDNA,HGLP, which encodes a G-protein coupled receptor (GPCR) like protein, has been isolated and cloned. The coding region of the humanHGLP predicts a 7-transmembrane region protein with motifs of rhodopsin-like GPCR superfamily. Northern blot analysis reveals a 3-kb transcript in various human tissues examined. The N- and C-terminal coding regions ofHGLP, which are deduced as non-transmembrane regions, have been amplified by PCR and cloned into pET30a+ vector. Then the recombinant proteins are highly expressed inE. coli.

Human nectin—like 1, a novel membrane protein interacting with protein 4.1 R

Human nectin—like 1 (NECL1) full—length cDNA was cloned by bioinformatics method when searching for candidate membrane proteins interacting with members of protein 4.1 family. The cytoplasmic and extracellular regions of NECLl were expressed in and purified from E.coli, and the polyclonal antibody was produced. Interaction between the cytoplasmic region of NECLl and the 30 kD membrane binding domain of protein 4.1 on red blood cell (4.1R) was demonstrated by IAsys—biosensor system and GST pull—down experiment. Results of biotin—labeled peptide ELISA further demonstrated the key amino acids for the binding. The interaction research of NECLls cytoplasmic domain provides basis for further study of the functions of NECL1 in nervous system. Supported by National Natural Science Foundation of China (Grant No. 50271027), Fujian International Cooperation Foundation (Grant No.20021018), and Fujian Natural Science Foundation (Grant Nos. E0310023 and 2002J010)

Cloning and identification of a novel human glioma differentiation related gene GDR1

In order to identify the genes associated with glioblastoma differentiation, some ESTs, expressed differentially in the control cell and the differentiated human glioblastoma cell line BT-325 induced by the all-trans retinoid acid, have been isolated by the method of DDRT-PCR. Of the 46 ESTs sequenced, 19 are from new genes. A full-length 1 535-bp cDNA, termed geneGDR1, has been isolated from the human cDNA library using the probe designed according to one of the novel ESTs, HGBB098. The open reading frame ofGDR1 gene encodes a putative protein containing 334 amino acid residues. Blast against the current GenBank DNA and protein sequence database did not reveal significant homology with any known proteins. RT-PCR shows thatGDR1 mRNA level increased in the differentiated BT-325 cells after being treated with RA. The different expression patterns ofGDR1 mRNA in human tissues have been detected through the multiple tissue Northern blot hybridization.