Domain conservation in several volvocalean cell wall proteins.
Based on our previous work demonstrating that (SerPro)x epitopes are common to extensin-like cell wall proteins in Chlamydomonas' reinhardtii, we looked for similar proteins in the distantly related species C. eugametos. Using a polyclonal antiserum against a (SerPro)10 oligopeptide, we found distinct sets of stage-specific polypeptides immunoprecipitated from in vitro translations of C. eugametos RNA. Screening of a C. eugametos cDNA expression library with the antiserum led to the isolation of a cDNA (WP6) encoding a (SerPro)x-rich multidomain wall protein. Analysis of a similarly selected cDNA (VSP-3) from a C. reinhardtii cDNA expression library revealed that it also coded for a (SerPro)x-rich multidomain wall protein. The C-terminal rod domains of VSP-3 and WP6 are highly homologous, while the N-terminal domains are dissimilar; however, the N-terminal domain of VSP-3 is homologous to the globular domain of a cell wall protein from Volvox carteri. Exon shuffling might be responsible for this example of domain conservation over 350 million years of volvocalean cell wall protein evolution.
Woessner
J P
JP
Department of Biology, Washington University, St. Louis, MO 63130.
Molendijk
A J
AJ
van Egmond
P
P
Klis
F M
FM
Goodenough
U W
UW
Haring
M A
MA
D020418:Algal Proteins; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002473:Cell Wall / Q000235:genetics*; D002696:Chlamydomonas / Q000235:genetics* / Q000254:growth & development; D003001:Cloning, Molecular; D017124:Conserved Sequence; D003429:Cross Reactions; D018076:DNA, Complementary / Q000235:genetics; D015870:Gene Expression; D016678:Genome; D006023:Glycoproteins / Q000235:genetics; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000276:immunology; D010940:Plant Proteins / Q000235:genetics* / Q000276:immunology; D014176:Protein Biosynthesis; D015800:Protozoan Proteins / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D016823:Volvocida / Q000235:genetics
D020418:Algal Proteins; D018076:DNA, Complementary; D006023:Glycoproteins; D009842:Oligopeptides; D010940:Plant Proteins; D015800:Protozoan Proteins; C091031:WP6 protein, Chlamydomonas eugametos; C005488:extensin protein, plant