A Cdc42-Borg4-Septin 7 axis regulates HSCs polarity and function

Autor: Schuster T, Yi Zheng, Katharina Senger, Sakk, Karin Soller, Manoj B. Menon, Hartmut Geiger, Karina Eiwen, Kandi R, Ani Grigoryan, Carolina Florian M, Matthias Gaestel
Rok vydání: 2021
Předmět:
Popis: Aging of hematopoietic stem cells (HSCs) is caused by an elevated activity of the small RhoGTPase Cdc42 and an apolar distribution of proteins. Mechanisms by which Cdc42 activity controls polarity of HSCs are not known. Binder of RhoGTPases proteins (borgs) are known effector proteins of Cdc42 that are able to regulate the cytoskeletal septin network. Here we show that Cdc42 interacts with borg4, which in turn interacts with septin 7 to regulate the polar distribution of Cdc42, borg4 and septin 7 within HSCs. Genetic deletion of either borg4 or septin 7 in HSCs resulted in a reduced frequency of HSCs polar for Cdc42 or borg4 or septin 7 and a reduced engraftment potential and decreased lymphoid-primed multipotent progenitors (LMPPs) frequency in the bone marrow. In aggregation our data identify a Cdc42-borg4-septin 7 axis to be essential for maintenance of polarity within HSCs and for HSC function and provide rationale for further investigating the role of borgs and septins for the regulation of compartmentalization within stem cells.Graphical Abstract
Databáze: OpenAIRE