Sequence analysis of DPDPª²2 gene cloned from human dental pulp cells

    WANG Zhongª²Dong1,3, GUO Hongª²Yan2, WU Jiª²Nan3, LING Junª²Qi1, XIAO Mingª²Zhen4, GUO Xiª²Min5, CHAI Yuª²Bo6

    1Guanghua Hospital of Stomatology, Sun Yatª²sen University, Guangzhou 510055, China, 2Department of Stomatology, General Hospital of Chinese People¬ðs Armed Police Forces, Beijing 100039, China, 3Dental Care Center, People¬ðs Hospital, Zhongshan, 528400, China, 4School of Stomatology, 6School of Basic Medicine, Fourth Military Medical University, Xi¬ðan 710033, China, 5Institute of Basic Medical Sciences, Academy of Military Medical Sciences, Beijing 100850, China

    ¡¾Abstract¡¿ AIM: To study the function of DPDPª²2, a new gene cloned from human dental pulp cell (HDPC). METHODS: A modified PCRª²based subtractive hybridization technique was used to establish a subtractive cDNA library. Genes differentially expressed in HPDC and human gingival fibroblasts (HGF) were cloned and sequenced. A new gene named DPDPª²2 was cloned and structural and functional analyses were performed by PC/GENE 6.60 software. RESULTS: The fragment of DPDPª²2 cloned from the present subtractive cDNA library was 810 bp, containing an incomplete coding region. However, after splicing with an EST sequence named KIAA0265, a 6172 bp complete cDNA sequence was achieved which encodes a 83aa hydrophobic protein with a secondary structure characterized by a helical conformation, an extended conformation and a coil conformation. The secondary structures could assemble a threeª²dimensional structure through folding of ¦Á, ¦Â or ¦Á/¦Â sheets. Antigen epitope analysis implied three possible antigenic determinants:Gluª²Asnª²Lysª²Argª²Thrª²Gly, Leuª²Ileª²Gluª²Argª²Leuª²Lys and Gluª²Leuª²Alaª²Trpª²Gluª²Lys. A transmembrane helical structure and a mitochondria transportation structure were also found. Signal peptide analysis further indicated that DPDPª²2 was a nonª²secretory protein. No homogeneous protein was found in Nonª²redundant SwissProt sequences and PDB protein database. CONCLUSION: DPDPª²2 encodes a transmembrane protein that has both signal transduction structural features and CKII phosphorylation site, indicating its possible functional relationship with cell mitosis and transcription. ......