Protein
Bud site selection protein 5
Organism
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Function
GDP-GTP exchange factor (GEF) for the small GTPase BUD1/RSR1. Regulates the activity of BUD1 together with BUD2 which is a GTPase-activating protein (GAP) of BUD1. Required to produce both the axial and bipolar patterns of bud site selection. Determines the orientation of division axis. Overexpression can suppress mutations in PRP20 which is the GEF for GSP1. May be a cytoplasmic GEF for GSP1. Might also act on the Ras-like protein CDC42. Appears to bind to Ras proteins but not to activate them.
Sequence
MSPKNKYVYICVEYIYIYFAKIHKQSTLSSDTTKMFVLIDNVLAYLLEQDDLFVTARFAIQGQIVSRRVNKIHISNITDVLLQQFISHTLPYNDNIVPKKILDSMRTAVRQLLEATACVSRECPLVKRSQDIKRARKRLLSDWYRLGADANMDAVLLVVNSAWRFLAVWRPFVNSIQHATQELYQNIAHYLLHGNVNIQRVTALIQLVMGQDDLLFSMDDVLQEVFRIQLYLNKMLPHNSHKWQKPSPFDSANLLLNFRDWTTDNALLQELLLSYPTINKNKHKNHSVPRLIQIWVESYWQDSETTLKDILNFWYSHLAEYYEYQELFADIVQLFINKKRTRQLKIHYIGLTDKEIEENKPPLDYENLFLQYEIDKTNANDELCGATDLSDLLFQWKQGELLEVEAFALNVSPWSLAKTLTLLESSLYLDIETIEFTRHFKHNDTTIDSVFTLSNQLSSYVLETTLQQTHTISYWLQVALSCLYLRNLNSLASIITSLQNHSIERLSLPIDVKSDHLFQRLKVVVHPNNNYNVYRRTIKHIFHSQLPCVPFTSLLIRDITFIRDGNDTFTKDGNNVNMQKFNQITKIVAFAQYLQQKQYEDIHCSNTTARSLLGAMIKVHTLYNDNKDRAYQVSIAKVPRLT