Cloning and characterization of a novel human secretory protein: secretogranin III.
We have cloned a new member of the granin family, termed human secretogranin III (SgIII), that encodes 468 amino acid residues. The human SgIII protein possesses an N-terminal signal peptide, seven dibasic sites, and the repeated DSTK sequences. These structure characteristics are similar to other members of secretogranin family. The human SgIII has homologous proteins in mouse, rat, and Xenopus laevis. Genomic organization shows the gene includes 12 coding exons spanning 39 kb of genomic DNA on the human chromosome 15. Human SgIII is expressed widely as showed in Northern blot and its cDNA hybridizes to 2.2 kb and 1.9 kb bands in many tissues, with two additional 4.5 kb and 3.3 kb bands in brain. Subcelluar localization and immunoblotting indicated SgIII was secreted out of cell through trans-Golgi network (TGN). SgIII may take effect in the biogenesis of secretory granules as a helper protein and be involved in the production or release of peptide hormones in the regulated secretory pathway.
Rong
Yi-Ping
YP
Research Institute of Biochemistry, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China. dzhwei@ecust.edu.cn
Liu
Feng
F
Zeng
Ling-Chun
LC
Ma
Wei-Jun
WJ
Wei
Dong-Zhi
DZ
Han
Ze-Guang
ZG
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019556:COS Cells; D002864:Chromogranins; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D005091:Exons; D005260:Female; D015870:Gene Expression; D005796:Genes / Q000235:genetics; D006801:Humans; D015151:Immunoblotting; D007438:Introns; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D011506:Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D002864:Chromogranins; D018076:DNA, Complementary; D011506:Proteins; D012333:RNA, Messenger