Structural and functional analyses of the PPIase domain of Arabidopsis thaliana CYP71 reveal its catalytic activity toward histone H3.
Arabidopsis thaliana CYP71 (AtCYP71) is a chromatin-remodeling protein that promotes shoot apical meristem (SAM) differentiation. The N terminus of AtCYP71 contains a noncanonical WD domain, and the C terminus contains an enzymatic peptidyl-prolyl isomerase (PPIase) cyclophilin (CYP) domain. To date, there has been no characterization of CYP71, and its mode of action remains unknown. Here, we report the crystal structure of the CYP domain of AtCYP71 at 1.9 Å resolution. The structure shows key differences when compared to the canonical CYP fold of human CypA. To the best our knowledge, this is the first A. thaliana CYP structure with a conserved active site loop. Using nuclear magnetic resonance spectroscopy, we demonstrate that the CYP domain is active toward histone H3. Our findings suggest that the PPIase activity of the CYP domain is important for the function of AtCYP71 in chromatin remodeling during organogenesis.
['Lakhanpal|Smarth|S|0000-0003-1713-6847', 'Fan|Jing-Song|JS|', 'Luan|Sheng|S|', 'Swaminathan|Kunchithapadam|K|']
D000595:Amino Acid Sequence D017360:Arabidopsis D029681:Arabidopsis Proteins D002384:Catalysis D018360:Crystallography, X-Ray D021983:Cyclophilins D006657:Histones D019906:Nuclear Magnetic Resonance, Biomolecular D019696:Peptidylprolyl Isomerase D011487:Protein Conformation D000072417:Protein Domains D017386:Sequence Homology, Amino Acid
PPIASE arabidopsis CYP71 shoot apical meristem genetic remodelling proline isomerisation structural biology