DelGEF, a homologue of the Ran guanine nucleotide exchange factor RanGEF, binds to the exocyst component Sec5 and modulates secretion.
In order to identify the function of deafness locus putative guanine nucleotide exchange factor (DelGEF), a protein homologous to the nucleotide exchange factor for the small GTPase Ran, a cDNA library was screened for interacting proteins using a yeast two-hybrid system. The human homologue of Sec5, a protein involved in vesicle transport and secretion, was identified as a binding partner. The interaction between DelGEF and Sec5 was found to be dependent on Mg2+ and stimulated by guanosine triphosphate (GTP) or deoxycytidine triphosphate (dCTP). Downregulation of endogenous DelGEF in HeLa cells induced increased extracellular secretion of proteoglycans indicating a possible role for DelGEF in the secretion process.
Sjölinder
Mikael
M
Division for Molecular Biology of Mitosis, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany.
Uhlmann
Jörg
J
Ponstingl
Herwig
H
D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D002412:Cations / Q000494:pharmacology; D015536:Down-Regulation; D005089:Exocytosis; D020662:Guanine Nucleotide Exchange Factors / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008670:Metals / Q000494:pharmacology; D008969:Molecular Sequence Data; D009711:Nucleotides / Q000494:pharmacology; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D011509:Proteoglycans / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D017385:Sequence Homology; D014018:Tissue Distribution; D020798:Two-Hybrid System Techniques; D033921:Vesicular Transport Proteins; D020931:ran GTP-Binding Protein / Q000378:metabolism
D002352:Carrier Proteins; D002412:Cations; C470182:EXOC2 protein, human; D020662:Guanine Nucleotide Exchange Factors; D008565:Membrane Proteins; D008670:Metals; D009711:Nucleotides; D016376:Oligonucleotides, Antisense; D011509:Proteoglycans; D012333:RNA, Messenger; C400705:SERGEF protein, human; D033921:Vesicular Transport Proteins; D020931:ran GTP-Binding Protein