title: Rapid centriole assembly in Naegleria reveals conserved roles for both de novo and mentored assembly.
abstract: Centrioles are eukaryotic organelles whose number and position are critical for cilia formation and mitosis. Many cell types assemble new centrioles next to existing ones ("templated" or mentored assembly). Under certain conditions, centrioles also form without pre-existing centrioles (de novo). The synchronous differentiation of Naegleria amoebae to flagellates represents a unique opportunity to study centriole assembly, as nearly 100% of the population transitions from having no centrioles to having two within minutes. Here, we find that Naegleria forms its first centriole de novo, immediately followed by mentored assembly of the second. We also find both de novo and mentored assembly distributed among all major eukaryote lineages. We therefore propose that both modes are ancestral and have been conserved because they serve complementary roles, with de novo assembly as the default when no pre-existing centriole is available, and mentored assembly allowing precise regulation of number, timing, and location of centriole assembly.
authors.affiliation: Department of Molecular and Cell Biology, University of California, Berkeley, California.|Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California.
authors.forename: Lillian K
authors.initials: LK
authors.lastname: Fritz-Laylin
authors.affiliation: Department of Biology, Brandeis University, Waltham, Massachusetts.
authors.forename: Yaron Y
authors.initials: YY
authors.lastname: Levy
authors.affiliation: Department of Biology, Brandeis University, Waltham, Massachusetts.
authors.forename: Edward
authors.initials: E
authors.lastname: Levitan
authors.affiliation: Department of Molecular and Cell Biology, University of California, Berkeley, California.
authors.forename: Sean
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Molecular and Cell Biology, University of California, Berkeley, California.
authors.forename: W Zacheus
authors.initials: WZ
authors.lastname: Cande
authors.affiliation: Department of Biology, Brandeis University, Waltham, Massachusetts.
authors.forename: Elaine Y
authors.initials: EY
authors.lastname: Lai
authors.affiliation: Department of Biology, Brandeis University, Waltham, Massachusetts.
authors.forename: Chandler
authors.initials: C
authors.lastname: Fulton
mesh_terms: D002502:Centrioles / Q000378:metabolism*; D019143:Evolution, Molecular; D008954:Models, Biological; D009253:Naegleria / Q000166:cytology / Q000378:metabolism*
keywords: Naegleria; basal bodies; centriole biogenesis; flagellum development