Source: Stowers Institute for Medical Research
Date: June 26, 2009
Summary:
The Stowers Institute's Xie Lab has revealed how the BAM protein affects germline stem cell differentiation and how it is involved in regulating the quality of stem cells through intercellular competition. The work was published today by PNAS Early Edition.
Maintaining the proper balance between stem cell self-renewal and differentiation is critical for normal homeostasis. An imbalance between the two can lead to tissue degeneration and to the development of tumors. It has long been known that the BAM protein is necessary for germline stem cell differentiation, but the specific molecular mechanism underlying BAM function had remained a mystery until now.
Examining the fruit fly ovary, the Xie Lab established that BAM controls stem cell differentiation and competition by interfering with the function of the protein translation initiation factor eIF4A. EIF4A and BAM antagonize each other to regulate the balance between self-renewal and differentiation by promoting proper expression of E-cadherin — a molecule crucial to the stem cell's ability to attach to its microenvironment (its niche).
