Molecular cloning and sequence determination of a cDNA coding for the alpha-subunit of a Go-type protein of Xenopus laevis oocytes.
Xenopus laevis oocytes are cells ideally suited to the study of signal transduction and of the G-proteins that are involved in this process. A X. laevis cDNA library in lambda gt10 has been screened with a mixture of three oligonucleotide probes designed to detect sequences found in various mammalian alpha-subunits of G-proteins. One of these clones has been purified through tertiary screening and the DNA insert has been sequenced. This clone was found to include the total sequence coding for a 354 amino acid protein that is 89% identical to the sequence of alpha-subunit of rat Go. The differences with the mammalian protein were clustered in amino acids 290-315, which have been postulated to define the region interacting with the receptor and effector molecule. The homology with the alpha-subunits of other mammalian G-proteins is lower (65-70% to Gi and 42% to Gs). On this basis, this clone can be classified as Go-like.
Olate
J
J
Departamento de Bioquímica, Facultad de Medicina, Universidad de Chile, Santiago.
Jorquera
H
H
Purcell
P
P
Codina
J
J
Birnbaumer
L
L
Allende
J E
JE
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D003062:Codon; D004247:DNA / Q000235:genetics*; D005260:Female; D019204:GTP-Binding Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes; D009865:Oocytes / Q000032:analysis*; D051381:Rats; D012689:Sequence Homology, Nucleic Acid; D014982:Xenopus laevis
D003062:Codon; D015345:Oligonucleotide Probes; D004247:DNA; D019204:GTP-Binding Proteins