Characterization of cis-acting element involved in cell cycle phase-independent activation of Arath;CycB1;1 transcription and identification of putative regulatory proteins.

摘要: Progression through the cell cycle is driven by cyclin-dependent kinases (CDKs) whose activity controlled regulatory subunits called cyclins. The expression of cyclins subject to numerous controls at multiple levels, not least level transcription. As a first step unravel mechanisms that regulate B-cyclins in plants, we undertook identification required promoter elements Arath;CycB1;1 gene. A detailed analysis different fragments consisted analysing their ability mediate cycle-dependent transcriptional oscillations gus reporter gene transformed BY-2 lines. We showed regions took part activation. Furthermore, 202 bp upstream ATG were sufficient induce M-phase-specific expression. This region contains an 18 sequence including Myb-binding core (AACGG) which able activate without leading Electrophoretic mobility shift assays this specifically binds protein complexes from Arabidopsis suspension enriched either G1 or G2 phase. Myb core, AACGG, was characterized as necessary for binding proteins. DNA affinity purification bound allowed isolation three and two proteins these identified mass spectrometry analyses. new putative transcription factor hypothetical protein, HYP containing with leucine zipper Myc-type dimerization domains identified. When over-expressed trans-activate downstream −202 fragment well endogenous CycB1;1