The Singularity of the Drosophila Male Germ Cell Centriole: The Asymmetric Distribution of Sas4 and Sas6.

Veronica Persico,Giuliano Callaini,Maria Giovanna Riparbelli,Massimo Migliorini

doi:10.3390/cells9010115

Abstract

Drosophila spermatocytes have giant centrioles that display unique properties. Both the parent centrioles maintain a distinct cartwheel and nucleate a cilium-like region that persists during the meiotic divisions and organizes a structured sperm axoneme. Moreover, the parent centrioles are morphologically undistinguishable, unlike vertebrate cells in which mother and daughter centrioles have distinct structural features. However, our immunofluorescence analysis of the parent centrioles in mature primary spermatocytes revealed an asymmetric accumulation of the typical Sas4 and Sas6 proteins. Notably, the fluorescence intensity of Sas4 and Sas6 at the daughter centrioles is greater than the intensity found at the mother ones. In contrast, the centrioles of wing imaginal disc cells display an opposite condition in which the loading of Sas4 and Sas6 at the mother centrioles is greater. These data underlie a subtle asymmetry among the parent centrioles and point to a cell type diversity of the localization of the Sas4 and Sas6 proteins.

Highlights

Centrioles are widely conserved barrel shaped organelles present in almost all the organisms.They are involved in the organization of the cytoplasmic microtubule network in interphase and during the cell division by recruiting the molecules need to their nucleation
The daughter centrioles are assembled in young Drosophila primary spermatocytes at right
We find the gold particles were found outside the centriole wall (Figure 2E) and inside the CLR lumen (Figure that the distribution of γ-tubulin to the centrioles of mature prophase spermatocytes was unperturbed by the inhibition of the Aurora A (Figure 3B; n = 94) and Polo/Plk1 (Figure 3C; n = 76) kinases, but γ-tubulin was found along the whole centrioles in mature primary spermatocytes with a distinct its accumulation at prometaphase was dramatically reduced following MLN8054 (Figure 3B’; n = 85)

Summary

Introduction

Centrioles are widely conserved barrel shaped organelles present in almost all the organisms. They are involved in the organization of the cytoplasmic microtubule network in interphase and during the cell division by recruiting the molecules need to their nucleation. The centrioles are required to assembly cilia and flagella [1]. The older mother centriole carries distal and subdistal appendages. The distal appendages mediate the docking to the cell membrane during primary cilia assembly [8] and immunological synapse formation [9]. The subdistal appendages play main roles in the recruitment of the pericentriolar material and the molecules need to assembly the cytoplasmic microtubule network in interphase and during cell division [10]

Methods

Results

Conclusion