GTP is required for the integration of a fragment of the Neurospora crassa H(+)-ATPase into homologous microsomal vesicles.
The integration of a fragment of the Neurospora crassa plasma membrane H(+)-ATPase was examined to determine if insertion of the fragment into homologous microsomal vesicles is obligatorily dependent on a nucleoside triphosphate. RNA transcripts that encoded the amino terminal 344 amino acids of the Neurospora crassa plasma membrane H(+)-ATPase(pma(344)+) were translated in a N. crassa in vitro system. The pma(344)+ integrated post-translationally into homologous microsomal vesicles independent of the associated ribosomes and dependent on the presence of GTP or guanylyl imidodiphosphate, a nonhydrolyzable analogue of GTP. ATP or analogues thereof did not support the integration of pma(344)+ into nRM post-translationally. These results were interpreted to suggest that a GTPase plays an essential role in the integration of the amino terminal portion of the pma+ into the endoplasmic reticulum.
Addison
R
R
Department of Biochemistry, University of Tennessee, Memphis 38163.
D000255:Adenosine Triphosphate / Q000494:pharmacology; D006160:Guanosine Triphosphate / Q000494:pharmacology*; D006165:Guanylyl Imidodiphosphate / Q000494:pharmacology; D007425:Intracellular Membranes / Q000201:enzymology; D008861:Microsomes / Q000201:enzymology*; D009492:Neurospora crassa / Q000201:enzymology*; D010957:Plasmids; D014176:Protein Biosynthesis; D011499:Protein Processing, Post-Translational; D006180:Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism*; D011691:Puromycin / Q000494:pharmacology; D012313:RNA / Q000235:genetics; D012270:Ribosomes / Q000378:metabolism; D014158:Transcription, Genetic
D006165:Guanylyl Imidodiphosphate; D011691:Puromycin; D012313:RNA; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D006180:Proton-Translocating ATPases