Identification of Genes Encoding CENP-A and Heterochromatin Protein 1 of Lipomyces starkeyi and Functional Analysis Using Schizosaccharomyces pombe

Genes (Basel). 2020 Jul 8;11(7):769. doi: 10.3390/genes11070769.

Abstract

Centromeres function as a platform for the assembly of multiple kinetochore proteins and are essential for chromosome segregation. An active centromere is characterized by the presence of a centromere-specific histone H3 variant, CENP-A. Faithful centromeric localization of CENP-A is supported by heterochromatin in almost all eukaryotes; however, heterochromatin proteins have been lost in most Saccharomycotina. Here, identification of CENP-A (CENP-AL.s.) and heterochromatin protein 1 (Lsw1) in a Saccharomycotina species, the oleaginous yeast Lipomyces starkeyi, is reported. To determine if these proteins are functional, the proteins in S. pombe, a species widely used to study centromeres, were ectopically expressed. CENP-AL.s. localizes to centromeres and can be replaced with S. pombe CENP-A, indicating that CENP-AL.s. is a functional centromere-specific protein. Lsw1 binds at heterochromatin regions, and chromatin binding is dependent on methylation of histone H3 at lysine 9. In other species, self-interaction of heterochromatin protein 1 is thought to cause folding of chromatin, triggering transcription repression and heterochromatin formation. Consistent with this, it was found that Lsw1 can self-interact. L. starkeyi chromatin contains the methylation of histone H3 at lysine 9. These results indicated that L. starkeyi has a primitive heterochromatin structure and is an attractive model for analysis of centromere heterochromatin evolution.

Keywords: CENP-A; centromere; heterochromatin; oleaginous yeast.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Centromere Protein A / genetics*
  • Centromere Protein A / metabolism
  • Chromosomal Proteins, Non-Histone / genetics*
  • Chromosomal Proteins, Non-Histone / metabolism
  • Cloning, Molecular
  • Fungal Proteins / genetics*
  • Fungal Proteins / metabolism
  • Lipomyces / genetics*
  • Protein Binding
  • Protein Domains
  • Schizosaccharomyces
  • Sequence Homology

Substances

  • Centromere Protein A
  • Chromosomal Proteins, Non-Histone
  • Fungal Proteins
  • heterochromatin-specific nonhistone chromosomal protein HP-1

Supplementary concepts

  • Lipomyces starkeyi