Xenopus laevis oocyte Gα subunits mRNAs Detection and quantitation during oogenesis and early embryogenesis by competitive reverse PCR

FEBS Letters

Oñate, Alejandro²  Antonelli, Marcelo³  Olate, Juan³  Birnbaumer, Lutz¹  Herrera, Luisa³ 

[1] Baylor College of Medicine, Department of Cell Biology, Texas Medical Center, Houston, 70030 TX, USA;Departamento de Immunologia, Universidad Austral de Valdivia, Valdivia, Chile;Departamento de Bioquímica, Universidad de Chile, Casilla 70086, Santiago 7, Chile

关键词: G-protein;    α subunit;    Signal transduction;    Oocyte;    Xenopus laevis;    PCR;   

DOI  :  10.1016/0014-5793(92)81194-Q

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The expression of mRNAs coding for different Xenopus laevis oocyte Gα subunits was analyzed by the PCR technique. Using the nucleotide sequences of five previously cloned cDNAs for oocyte Gα subunits [FEBS Lett. 244, 188–192, 1989; FEBS Lett. 268, 27–31, 1990] and the highly sensitive reverse PCR reaction we found that Gαo, Gαi-1, Gαi-3 and Gαs species are present in oocyte stage VI, Gαo mRNA being the most abundant transcript. Gαo mRNA was further quantitated through oogenesis, unfertilized eggs and early embryogenesis stages by a competitive PCR reaction using an ‘in vitro’ deleted Gαo mRNA as the internal standard. Using this approach we found that Xenopus Gαo mRNA levels were constant during oogenesis and unfertilized eggs at a concentration of 3.5 pg of mRNA/stage (5 × 10⁵ molecules) and diminish gradually during early embryogenesis, reaching a level of 0.3 pg in the gastrula stage. These findings show that oocyte Gαo, and perhaps the rest of the α subunits, are expressed as maternal mRNAs and could play an important role in signal transduction at the beginning of oocyte cell differentiation.

【 授权许可】

Unknown