TY - JOUR
T1 - Cloning and expression of a gene encoding an integrin-like protein in Candida albicans
AU - Gale, Cheryl
AU - Finkel, David
AU - Tao, Nianjun
AU - Meinke, Marilyn
AU - McClellan, Mark R
AU - Olson, Jennifer
AU - Kendrick, Kathleen
AU - Hostetter, Margaret
PY - 1996/1/9
Y1 - 1996/1/9
N2 - The existence of integrin-like proteins in Candida albicans has been postulated because monoclonal antibodies to the leukocyte integrins αM and αX bind to blastospores and germ tubes, recognize a candidal surface protein of κ 185 kDa, and inhibit candidal adhesion to human epithelium. The gene αINT1 was isolated from a library of C. albicans genomic DNA by screening with a cDNA probe from the transmembrane domain of human αM. The predicted polypeptide (αInt1p) of 188 kDa contains several motifs common to αM and αX: a putative I domain, two EF-hand divalent cation-binding sites, a transmembrane domain, and a cytoplasmic tail with a single tyrosine residue. An internal RGD tripeptide is also present. Binding of anti-peptide antibodies raised to potential extracellular domains of αInt1p confirms surface localization in C. albicans blastospores. By Southern blotting, αINT1 is unique to C. albicans. Expression of αINT1 under control of a galactose-inducible promoter led to the production of germ tubes in haploid Saccharomyces cerevisiae and in the corresponding ste12 mutant. Germ tubes were not observed in haploid yeast transformed with vector alone, in transformants expressing a galactose-inducible gene from Chlamydomonas, or in transformants grown in the presence of glucose or raffinose. Transformants producing αInt1p bound an anti-αM monoclonal antibody and exhibited enhanced aggregation. Studies of αInt1p reveal novel roles for primitive integrin-like proteins in adhesion and in STE12-independent morphogenesis.
AB - The existence of integrin-like proteins in Candida albicans has been postulated because monoclonal antibodies to the leukocyte integrins αM and αX bind to blastospores and germ tubes, recognize a candidal surface protein of κ 185 kDa, and inhibit candidal adhesion to human epithelium. The gene αINT1 was isolated from a library of C. albicans genomic DNA by screening with a cDNA probe from the transmembrane domain of human αM. The predicted polypeptide (αInt1p) of 188 kDa contains several motifs common to αM and αX: a putative I domain, two EF-hand divalent cation-binding sites, a transmembrane domain, and a cytoplasmic tail with a single tyrosine residue. An internal RGD tripeptide is also present. Binding of anti-peptide antibodies raised to potential extracellular domains of αInt1p confirms surface localization in C. albicans blastospores. By Southern blotting, αINT1 is unique to C. albicans. Expression of αINT1 under control of a galactose-inducible promoter led to the production of germ tubes in haploid Saccharomyces cerevisiae and in the corresponding ste12 mutant. Germ tubes were not observed in haploid yeast transformed with vector alone, in transformants expressing a galactose-inducible gene from Chlamydomonas, or in transformants grown in the presence of glucose or raffinose. Transformants producing αInt1p bound an anti-αM monoclonal antibody and exhibited enhanced aggregation. Studies of αInt1p reveal novel roles for primitive integrin-like proteins in adhesion and in STE12-independent morphogenesis.
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U2 - 10.1073/pnas.93.1.357
DO - 10.1073/pnas.93.1.357
M3 - Article
C2 - 8552638
AN - SCOPUS:0030029971
SN - 0027-8424
VL - 93
SP - 357
EP - 361
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 1
ER -