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Repression of Abd-B by Polycomb is critical for cell identity maintenance in adult Drosophila testis.

ABSTRACT: Hox genes play a fundamental role in regulating animal development. However, less is known about their functions on homeostasis maintenance in adult stem cells. Here, we report that the repression of an important axial Hox gene, Abdominal-B (Abd-B), in cyst stem cells (CySCs) is essential for the homeostasis and cell identity maintenance in the adult Drosophila testis. Derepression of Abd-B in CySCs disrupts the proper self-renewal of both germline stem cells (GSCs) and CySCs, and leads to an excessive expansion of early stage somatic cells, which originate from both lineages. We further demonstrate that canonical Polycomb (Pc) and functional pathway of Polycomb group (PcG) proteins are responsible for maintaining the germline cell identity non-autonomously via repressing Abd-B in CySCs in the adult Drosophila testis.

SUBMITTER: Zhang S

PROVIDER: S-EPMC5506049 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Repression of Abd-B by Polycomb is critical for cell identity maintenance in adult Drosophila testis.

Zhang Shuo S Pan Chenyu C Lv Xiangdong X Wu Wei W Chen Hao H Wu Wenqing W Wu Hailong H Zhang Lei L Zhao Yun Y

Scientific reports 20170711 1

Hox genes play a fundamental role in regulating animal development. However, less is known about their functions on homeostasis maintenance in adult stem cells. Here, we report that the repression of an important axial Hox gene, Abdominal-B (Abd-B), in cyst stem cells (CySCs) is essential for the homeostasis and cell identity maintenance in the adult Drosophila testis. Derepression of Abd-B in CySCs disrupts the proper self-renewal of both germline stem cells (GSCs) and CySCs, and leads to an ex ...[more]

PMID: 28698559

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