High impact information on E2F1

• The role of the Arabidopsis E2FB transcription factor in regulating auxin-dependent cell division [1].
• We conclude that E2FB is one of the key targets for auxin to determine whether cells proliferate or whether they exit the cell cycle, enlarge, and endoreduplicate their DNA [1].
• Coexpression of E2FB, but not of E2FA, with its dimerization partner A, stimulated cell proliferation in the absence of auxin in tobacco (Nicotiana tabacum) Bright Yellow-2 cells [1].
• Increased E2FB levels led to shortened cell cycle duration, elevated cell numbers, and extremely small cell sizes [1].
• In the absence of auxin, cells elongated with concomitant increase in their ploidy level, but both were strongly inhibited by E2FB [1].

Biological context of E2F1

• Both AtE2F1 and AtE2F3 were translocated to the nucleus and transactivate an E2F reporter gene when co-expressed with DPa but not DPb [2].
• Because the DNA binding activities of the three E2Fs are equally stimulated by the interaction with DPa or DPb in vitro, the observed transactivation of AtE2F1 and AtE2F3 is DPa specific and nuclear import dependent [2].

Associations of E2F1 with chemical compounds

• Here, we show that in Arabidopsis thaliana E2FB, accumulation and stability are positively regulated by auxin [1].

Other interactions of E2F1

• E2FB regulated the entry into both S- and M-phases, the latter corresponding to the activation of a plant-specific mitotic regulator, CDKB1;1 [1].

References