Fig. 7: Blue light positively regulates LRBs protein abundance in plants.
From: Regulation of Arabidopsis photoreceptor CRY2 by two distinct E3 ubiquitin ligases
a A hypothetic model depicting the degradation of CRY2 by LRBs and COP1 E3 ubiquitin ligases. CRY2 exists as inactive monomers in darkness (grey). Upon blue light exposure, CRY2 undergoes photoexcitation, oligomerization, and phosphorylation to become photoactive. Photoactivated CRY2 then were targeted by two distinct E3 ubiquitin ligases, LRBs, and COP1, for degradation. Minus sign in a circle, indicates negative charge; dashed line, indicates a hypothetical mechanism. b–e Representative immunoblots (top) and a quantitative analysis (bottom) showing the expression of recombinant LRB proteins in transgenic plants driven by native promoters (b, d) or the ACT2 constitutive promoter (c, e). Seedlings were grown in darkness or continuous blue light (50 μmol m−2 s−1) for 5, 6, or 7 days. Proteins were extracted and subjected to western blot analysis. LRBs and HSP90 were detected with anti-Flag and anti-HSP90 antibodies, respectively. HSP90 is used as a loading control. Data were shown as mean ± SD (n = 3 individual immunoblots). The above experiments were repeated at least three times with similar results.
