Mutation of the gene for the second-largest subunit of RNA polymerase I prolongs the period length of the circadian conidiation rhythm in Neurospora crassa.
Onai K., Katagiri S., Akiyama M., Nakashima H.
The period length of the circadian conidiation rhythm was examined in a mutant strain of Neurospora crassa, un-18, that is temperature sensitive for mycelial growth. The un-18 mutant showed a temperature-sensitive phenotype with respect to both mycelial growth and the period length of the conidiation rhythm. Below 22 degrees C, the un-18 mutation did not affect the period length, but at temperatures between 22 degrees C and 32 degrees C, the period length of the un-18 mutant was approximately 2 h longer than that of the wild-type strain. The un-18+ gene was cloned and was found to encode the second-largest subunit of RNA polymerase I, which is involved in the synthesis of rRNA. These results indicate that a defect in ribosome synthesis, which must result in a lower rate of protein synthesis, lengthens the period of the circadian conidiation rhythm in Neurospora.
Mol. Gen. Genet. 259:264-271(1998) [ PubMed | SRS | CiteXplore ]
