The C-terminal domain of B-Myb acts as a positive regulator of transcription and modulates its biological functions.
The C-terminal domain of B-Myb acts as a positive regulator of transcription and modulates its biological functions.
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B-Myb 的 C 端结构域充当转录的正调节因子并调节其生物学功能。
DOI：
10.1128/mcb.18.1.499
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发表时间：
1998
影响因子：
5.3
通讯作者：
Reddy,EP
中科院分区：
文献类型：
--
作者：
Oh,IH;Reddy,EP
Themybgene family consists of three members, named A-, B-, and c-myb. All three members of this family encode nuclear proteins that bind DNA in a sequence-specific manner and function as regulators of transcription. In this report, we have examined the biochemical and biological activities of murine B-myband compared these properties with those of murine c-myb. In transient transactivation assays, murine B-mybexhibited transactivation potential comparable to that of c-myb. An analysis of deletion mutants of B-myband c-mybshowed that while the C-terminal domain of c-Myb acts as a negative regulator of transcriptional transactivation, the C-terminal domain of B-Myb functions as a positive enhancer of transactivation. To compare the biological activities of c-myband B-myb, the two genes were overexpressed in 32Dcl3 cells, which are known to undergo terminal differentiation into granulocytes in the presence of granulocyte colony-stimulating factor (G-CSF). We observed that c-mybblocked the G-CSF-induced terminal differentiation of 32Dcl3 cells, resulting in their continued proliferation in the presence of G-CSF. In contrast, ectopic overexpression of B-mybblocked the ability of 32D cells to proliferate in the presence of G-CSF and accelerated the G-CSF-induced granulocytic differentiation of these cells. Similar studies with B-myb–c-mybchimeras showed that only chimeras that contained the C-terminal domain of B-Myb were able to accelerate the G-CSF-induced terminal differentiation of 32Dcl3 cells. These studies show that c-myband B-mybdo not exhibit identical biological activities and that the carboxyl-terminal regulatory domain of B-Myb plays a critical role in its biological function.
