Hsec22c: a homolog of yeast Sec22p and mammalian rsec22a and msec22b/ERS-24.
We have cloned a new member of a family of mammalian proteins homologous to Sec22p, a v-SNARE in Saccharomyces cerevisiae required for transport between the endoplasmic reticulum (ER) and the Golgi apparatus. The open reading frame encodes a polypeptide of 250 amino acids which is homologous to, but obviously different from, the recently reported mammalian Sec22p homologs rat sec22a, mouse sec22b, and hamster ERS-24. Northern blot analysis revealed two transcripts of about 1 and 5 kb respectively which are ubiquitously expressed. myc-epitope tagged sec22c is localized to the ER. Overexpression of the myc-tagged protein resulted in an anomalous staining pattern of SNARE molecules participating in ER-Golgi transport such as syntaxin 5 and mammalian bet1, but not the endosomal SNARE syntaxin 7. The presence of multiple forms of sec22 protein in the mammalian early secretory pathway is in-line with task specification in a highly elaborate transport machinery.
Tang
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BL
Membrane Biology Laboratory, Institute of Molecular and Cell Biology, Singapore, Republic of Singapore.
Low
D Y
DY
Hong
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W
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001692:Biological Transport; D015152:Blotting, Northern; D003001:Cloning, Molecular; D004247:DNA / Q000737:chemistry; D004721:Endoplasmic Reticulum / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D005656:Fungal Proteins; D006056:Golgi Apparatus / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D050683:R-SNARE Proteins; D011956:Receptors, Cell Surface / Q000737:chemistry* / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000737:chemistry; D029701:Saccharomyces cerevisiae Proteins; D017385:Sequence Homology
D005656:Fungal Proteins; D050683:R-SNARE Proteins; D011956:Receptors, Cell Surface; D029701:Saccharomyces cerevisiae Proteins; C106909:Sec22 protein, S cerevisiae; D004247:DNA