Potential Roles For C-Myb Thoughout Early Lymphocyte Development

Expression of the c-Myb transcription factor is primarily associated with the immature stages of haemopoietic differentiation and expression is down regulated to low or undetectable levels as haemopoietic maturation progresses. During lymphocyte development, c-Myb is abundantly expressed in early precursors and down regulation of c-Myb expression appears to occur near or during the time of repertoire selection. This pattern of expression has long suggested a significant role for c-Myb during lymphocyte development, which has been provocatively reinforced by reports of putative c-Myb target genes that are crucial for lymphocyte development. However, gaining insight has been greatly impeded by the embryonic lethality of traditional null c-myb mutations and the lack of a tractable genetic model to study c-Myb function. This chapter will discuss the relationship between c-Myb and lymphocyte development and discuss the prospect of gaining insight into c-Myb activity using conditional approaches to gene targetting.