Early Diverging Fungus Mucor circinelloides Lacks Centromeric Histone CENP-A and Displays a Mosaic of Point and Regional Centromeres.

Published

Journal Article

Centromeres are rapidly evolving across eukaryotes, despite performing a conserved function to ensure high-fidelity chromosome segregation. CENP-A chromatin is a hallmark of a functional centromere in most organisms. Due to its critical role in kinetochore architecture, the loss of CENP-A is tolerated in only a few organisms, many of which possess holocentric chromosomes. Here, we characterize the consequence of the loss of CENP-A in the fungal kingdom. Mucor circinelloides, an opportunistic human pathogen, lacks CENP-A along with the evolutionarily conserved CENP-C but assembles a monocentric chromosome with a localized kinetochore complex throughout the cell cycle. Mis12 and Dsn1, two conserved kinetochore proteins, were found to co-localize to a short region, one in each of nine large scaffolds, composed of an ∼200-bp AT-rich sequence followed by a centromere-specific conserved motif that echoes the structure of budding yeast point centromeres. Resembling fungal regional centromeres, these core centromere regions are embedded in large genomic expanses devoid of genes yet marked by Grem-LINE1s, a novel retrotransposable element silenced by the Dicer-dependent RNAi pathway. Our results suggest that these hybrid features of point and regional centromeres arose from the absence of CENP-A, thus defining novel mosaic centromeres in this early-diverging fungus.

Full Text

Duke Authors

Cited Authors

  • Navarro-Mendoza, MI; Pérez-Arques, C; Panchal, S; Nicolás, FE; Mondo, SJ; Ganguly, P; Pangilinan, J; Grigoriev, IV; Heitman, J; Sanyal, K; Garre, V

Published Date

  • November 18, 2019

Published In

Volume / Issue

  • 29 / 22

Start / End Page

  • 3791 - 3802.e6

PubMed ID

  • 31679929

Pubmed Central ID

  • 31679929

Electronic International Standard Serial Number (EISSN)

  • 1879-0445

Digital Object Identifier (DOI)

  • 10.1016/j.cub.2019.09.024

Language

  • eng

Conference Location

  • England