The SPS100 gene of Saccharomyces cerevisiae is activated late in the sporulation process and contributes to spore wall maturation

Mol Cell Biol. 1988 Feb;8(2):912-22. doi: 10.1128/mcb.8.2.912-922.1988.

Abstract

We previously described the use of a differential hybridization screen of a genomic DNA library of Saccharomyces cerevisiae to identify sporulation-specific (SPS) genes (A. Percival-Smith and J. Segall, Mol. Cell. Biol. 4:142-150, 1984). This initial screen identified 14 SPS genes that are first expressed 6 to 8 h after transfer of cells to sporulation medium. Accumulation of transcripts corresponding to these genes becomes maximal at 8 to 12 h of sporulation, the time at which meiotic events are nearing completion, and by 15 h of sporulation, transcript levels are beginning to decrease. In the present study two additional SPS genes, first expressed at 12 h of sporulation, were isolated. The steady-state level of transcripts corresponding to these two genes, termed SPS100 and SPS101, remains unchanged from 15 to 35 h, a time coincident with spore wall maturation. The nature of the putative 34.2-kilodalton protein encoded by the SPS100 gene is consistent with its being a component of the glycoprotein matrix of the spore wall; the protein contains a potential signal sequence and cleavage site and numerous sites for potential glycosylation. A MATa sps100/MAT alpha sps100 strain was found to be indistinguishable from the wild-type strain when assessed for efficiency of ascus formation and spore viability. However, a more detailed analysis of the mutant strain revealed that the SPS100 gene product serves a protective role during the early stages of spore wall formation. The time at which resistance to ether could first be detected in developing spores was delayed by 5 h in the mutant strain relative to the wild-type strain. This phenotype is presumably a reflection of a defect in spore wall maturation. This study has confirmed that temporally distinct classes of sporulation-specific genes are sequentially activated during the process of meiosis and spore formation and has shown that the SPS100 gene, identified on the basis of its developmental-specific expression pattern, contributes to spore development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cell Wall / physiology
  • Chromosome Deletion
  • DNA, Fungal / genetics
  • Gene Expression Regulation*
  • Genes*
  • Genetic Vectors
  • Molecular Sequence Data
  • Nucleic Acid Hybridization
  • Plasmids
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / physiology
  • Spores, Fungal / physiology
  • Transcription, Genetic

Substances

  • DNA, Fungal

Associated data

  • GENBANK/M20366