MOLECULAR-CLONING AND DERIVED PRIMARY STRUCTURE OF COBRA VENOM FACTOR

被引:61
作者
FRITZINGER, DC
BREDEHORST, R
VOGEL, CW
机构
[1] GEORGETOWN UNIV, DEPT MED, DEPT BIOCHEM & MOLEC BIOL, WASHINGTON, DC 20007 USA
[2] GEORGETOWN UNIV, CTR INTERDISCIPLINARY RES IMMUNOL DIS, WASHINGTON, DC 20007 USA
[3] UNIV HAMBURG, DEPT BIOCHEM & MOLEC BIOL, D-20146 HAMBURG, GERMANY
关键词
COMPLEMENT SYSTEM; COMPLEMENT COMPONENT C3; POSTTRANSLATIONAL PROCESSING; CDNA CLONING;
D O I
10.1073/pnas.91.26.12775
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
Cobra venom factor (CVF) is the complement-activating protein in cobra venom. Like C3b, CVF forms with factor B and factor D in human and mammalian serum the bimolecular C3/C5 convertase. This functional similarity of CVF and C3 correlates with many structural similarities, which led to the suggestion that CVF is evolutionally related to C3. We report here the molecular cloning and derived primary structure of CVF. CVF mRNA is >5924 nucleotides in length. It contains a single open reading frame of 4926 nucleotides, coding for a pre-pro-protein of 1642 amino acids. The deduced amino acid sequence reveals approximate to 70% protein similarity to mammalian and human C3 and exceeds 91% in the case of cobra C3. The single-chain pre-pro CVF consists of a 22-amino acid signal sequence, a 627-amino acid alpha-chain, and a 989-amino acid precursor chain for the CVF gamma- and beta-chains. The processing of pro-CVF involves the removal of 4 arginine residues between the alpha- and precursor chains as well as of the C3a-like and C3d-like domains from the precursor chain, thereby confirming the predicted chain homologies to C3. Pro-CVF contains five potential N-glycosylation sites, of which only three can be expected to be glycosylated in mature CVF. Like C3, pro-CVF contains 27 cysteine residues and a homologous thioester site in the C3d-like region.
引用
收藏
页码:12775 / 12779
页数:5
相关论文
共 21 条
  • [1] COBRA VENOM FACTOR - EVIDENCE FOR ITS BEING ALTERED COBRA C3 (3RD COMPONENT OF COMPLEMENT)
    ALPER, CA
    BALAVITCH, D
    [J]. SCIENCE, 1976, 191 (4233) : 1275 - 1276
  • [2] BECHERER JD, 1988, J BIOL CHEM, V263, P14586
  • [3] COCHRANE CG, 1970, J IMMUNOL, V105, P55
  • [4] DAOUDAKI ME, 1988, J IMMUNOL, V140, P1577
  • [5] DEBRUIJN MHL, 1985, P NATL ACAD SCI USA, V82, P708
  • [6] DISULFIDE BRIDGES IN HUMAN-COMPLEMENT COMPONENT C3B
    DOLMER, K
    SOTTRUPJENSEN, L
    [J]. FEBS LETTERS, 1993, 315 (01) : 85 - 90
  • [7] MOLECULAR CHARACTERIZATION OF THE COMPLEMENT ACTIVATING PROTEIN IN THE VENOM OF THE INDIAN COBRA (NAJA-N-SIAMENSIS)
    EGGERTSEN, G
    LIND, P
    SJOQUIST, J
    [J]. MOLECULAR IMMUNOLOGY, 1981, 18 (02) : 125 - 133
  • [8] FRITZINGER DC, 1992, J IMMUNOL, V149, P3554
  • [9] GANU V S, 1985, Complement, V2, P27
  • [10] GOWDA DC, 1994, J IMMUNOL, V152, P2977