The nucleotide sequence of a third cyclophilin-homologous gene from Saccharomyces cerevisiae.
The nucleotide sequence of a 1558 bp DNA fragment from the right arm of chromosome III of Saccharomyces cerevisiae contains an open reading frame of 954 nucleotides with coding potential for a protein with high similarity to the ubiquitous cyclophilins which are both peptidyl-prolyl cis-trans isomerases and cyclosporin A-binding proteins. It should, therefore, represent the third gene (SCC3) of this kind from S. cerevisiae. SCC3 is present in a single copy in the genome of S. cerevisiae and results in a constitutively expressed 1.2 kb transcript during cell growth. Its putative protein product (Scc3) contains two hydrophobic cores, one at the amino terminal, 20 amino acids long, which could serve as a signal peptide, and the other one at the carboxyl end with a structure similar to a transmembrane helix. These findings suggest that Scc3 could be a secretory or, more likely, a transmembrane protein. The only cyclophilin with similar structure to that of Scc3 is ninaA from Drosophila melanogaster, a transmembrane protein which seems to be implicated in the correct folding and/or intercalation of rhodopsin in the endoplasmic reticulum of the fly photoreceptors (Stamnes, M.A. et al., Cell 65, 219-227, 1991). In addition, the amino and the carboxy regions of Scc3 and ninaA share a significant level of homology, which suggests that they have a similar function, albeit for different target proteins.
Franco
L
L
Centro de Biología Molecular (C.S.I.C./U.A.M.), Universidad Autónoma, Madrid, Spain.
Jiménez
A
A
Demolder
J
J
Molemans
F
F
Fiers
W
W
Contreras
R
R
D000591:Amino Acid Isomerases / Q000737:chemistry / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics*; D003001:Cloning, Molecular; D003524:Cyclosporins / Q000737:chemistry / Q000235:genetics*; D004271:DNA, Fungal / Q000032:analysis / Q000737:chemistry*; D004331:Drosophila melanogaster / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D019696:Peptidylprolyl Isomerase; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000235:genetics*
D002352:Carrier Proteins; D003524:Cyclosporins; D004271:DNA, Fungal; D000591:Amino Acid Isomerases; D019696:Peptidylprolyl Isomerase