Send to:

Choose Destination
See comment in PubMed Commons below
Mol Cell Biol. 1993 Jan;13(1):28-38.

Characterization of HIR1 and HIR2, two genes required for regulation of histone gene transcription in Saccharomyces cerevisiae.

Author information

  • 1Program in Molecular Biology, Sloan Kettering Cancer Center, New York, New York.


The products of the HIR1 and HIR2 genes have been defined genetically as repressors of histone gene transcription in S. cerevisiae. A mutation in either gene affects cell cycle regulation of three of the four histone gene loci; transcription of these loci occurs throughout the cell cycle and is no longer repressed in response to the inhibition of DNA replication. The same mutations also eliminate autogenous regulation of the HTA1-HTB1 locus by histones H2A and H2B. The HIR1 and HIR2 genes have been isolated, and their roles in the transcriptional regulation of the HTA1-HTB1 locus have been characterized. Neither gene encodes an essential protein, and null alleles derepress HTA1-HTB1 transcription. Both HIR genes are expressed constitutively under conditions that lead to repression or derepression of the HTA1 gene, and neither gene regulates the expression of the other. The sequence of the HIR1 gene predicts an 88-kDa protein with three repeats of a motif found in the G beta subunit of retinal transducin and in a yeast transcriptional repressor, Tup1. The sequence of the HIR2 gene predicts a protein of 98 kDa. Both gene products contain nuclear targeting signals, and the Hir2 protein is localized in the nucleus.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk