Tissue specific requirement of Drosophila Rcd4 for centriole duplication and ciliogenesis.

Pallavi Panda,David M Glover,Giuliano Callaini,Levente Kovacs,Maria Giovanna Riparbelli,Agnieszka Fatalska,Marco Geymonat,Nikola Dzhindzhev,Veronica Persico

doi:10.1083/jcb.201912154

Abstract

Rcd4 is a poorly characterized Drosophila centriole component whose mammalian counterpart, PPP1R35, is suggested to function in centriole elongation and conversion to centrosomes. Here, we show that rcd4 mutants exhibit fewer centrioles, aberrant mitoses, and reduced basal bodies in sensory organs. Rcd4 interacts with the C-terminal part of Ana3, which loads onto the procentriole during interphase, ahead of Rcd4 and before mitosis. Accordingly, depletion of Ana3 prevents Rcd4 recruitment but not vice versa. We find that neither Ana3 nor Rcd4 participates directly in the mitotic conversion of centrioles to centrosomes, but both are required to load Ana1, which is essential for such conversion. Whereas ana3 mutants are male sterile, reflecting a requirement for Ana3 for centriole development in the male germ line, rcd4 mutants are fertile and have male germ line centrioles of normal length. Thus, Rcd4 is essential in somatic cells but is not absolutely required in spermatogenesis, indicating tissue-specific roles in centriole and basal body formation.

Highlights

Centrioles are the core components of centrosomes and trans- centriole duplication
Cells were immuno-stained to reveal GFP relative to zone I marker Sas6 and zone III marker Drosophila pericentrin-like protein (D-Plp), n = 19 centrosomes scored in control double-stranded RNAs (dsRNA)-treated cells and n = 24 centrosomes scored in Ana3 dsRNA-treated cells; N = at least three times
Cells were immuno-stained to reveal GFP, Sas6, and D-Plp, n = 25 centrosomes scored in control dsRNA-treated cells and n = 19 centrosomes scored in Rcd4 dsRNA-treated cells; N = at least three times

Summary

Introduction

Centrioles are the core components of centrosomes and trans- centriole duplication Defects in their et al, 2005); Sas corresponds to anastral spindle (Ana) 2 in structure, function, and duplication have an impact upon many flies and SCL/TAL1 interrupting locus (STIL) in humans aspects of biology ranging from cell division to cellular and de- Another genome-wide screen confirmed the identity of many Drosophila genes required for centriole/centrosome functions and identified some new participants in these roles (Dobbelaere et al, 2008). We show that Rcd and Ana directly interact to form a heterodimeric complex and that the timing of its recruitment to the centriole suggests a role in centriole to centrosome conversion

Results

Discussion

Findings

Materials and methods