Open AccessPosition-dependent and -independent mechanisms regulate cell-specific expression of the SpoC1 gene cluster of Aspergillus nidulans.
Author(s) -
Bruce L. Miller,
Karen Y. Miller,
K A Roberti,
William E. Timberlake
Publication year - 1987
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.7.1.427
Subject(s) - conidiation , aspergillus nidulans , biology , gene , gene expression , hypha , gene cluster , regulation of gene expression , microbiology and biotechnology , genetics , fungal protein , mutant
Many genes that are expressed specifically in the differentiating asexual spores (conidia) of Aspergillus nidulans are organized into clusters. We investigated the effects of altered chromosomal position on expression of a gene from the conidiation-specific SpoC1 gene cluster. The gene became deregulated when integrated at nonhomologous chromosomal sites, in that transcript levels were elevated in vegetative cells (hyphae) and variably altered in conidia. We also investigated the effects on expression of insertion of the nonregulated argB gene into the SpoC1 region. Levels of argB transcripts were markedly reduced in hyphae. The results suggest that a cis-acting regional regulatory mechanism represses transcription of SpoC1 genes in hyphae. They also indicate that expression of individual SpoC1 genes is modulated during conidiation by trans-acting factors. We propose that the two types of regulation act together to produce the major differences in transcript levels observed in hyphae versus conidia.