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Neurospora crassa A mating-type region.

ABSTRACT: The mating-type locus of the haploid filamentous fungus Neurospora crassa is a regulatory region that controls entry into the sexual cycle and prevents formation of mixed mating-type heterokaryons in the vegetative phase. The locus consists of alternative sequences called A and a. The A mating-type DNA sequence of Neurospora crassa is composed of a region of 5301 base pairs that has little similarity to the sequence present at the mating-type locus in an a mating-type strain. However, the sequences flanking the mating-type locus in the A haploid and a haploid genome are essentially identical. The region of the A mating-type sequence required for expression of the heterokaryon incompatibility and sexual functions has been localized to a single open reading frame (ORF) encoding a polypeptide of 288 amino acids. Sequence analysis of sterile, heterokaryon-compatible mutants reveals frameshift mutations in this same ORF. The putative 288-amino acid product has a region of similarity to the MAT alpha 1 polypeptide of Saccharomyces cerevisiae.

SUBMITTER: Glass NL

PROVIDER: S-EPMC54231 | biostudies-other | 1990 Jul

REPOSITORIES: biostudies-other

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Neurospora crassa A mating-type region.

Glass N L NL Grotelueschen J J Metzenberg R L RL

Proceedings of the National Academy of Sciences of the United States of America 19900701 13

The mating-type locus of the haploid filamentous fungus Neurospora crassa is a regulatory region that controls entry into the sexual cycle and prevents formation of mixed mating-type heterokaryons in the vegetative phase. The locus consists of alternative sequences called A and a. The A mating-type DNA sequence of Neurospora crassa is composed of a region of 5301 base pairs that has little similarity to the sequence present at the mating-type locus in an a mating-type strain. However, the sequen ...[more]

PMID: 2142303

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Heterochromatin controls γH2A localization in Neurospora crassa.

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