Fig. 5

OsCCRL1 process the CCR enzyme activity and is involved in phenylpropane metabolism and tapetum apoptosis. A The comparison of extracted CCRs enzyme activity in the wild type and osccrl1 mutant anthers. Data are means ± SD (n = 3). B The lignin staining of wild-type and osccrl1 anthers by phloroglucinol-HCl. Bars, 20 μm (left) and 80 μm (right). C The lignin content of wild-type and osccrl1 spikelets extracted by thioglycolic acid-HCl. Asterisks indicate the significance differences determined by Student’s t-test (*, 0.01 ≤ P < 0.05; **, P < 0.01). D In vitro enzyme activity of OsCCRL1 and osccrl1 proteins. Data are means ± SD (n = 3). E − G The relative expression comparison of Os4CL3, OsCHS1 and OsCCRL1 in the wild type and osccrl1 anthers. Data are means ± SD (n = 3). Asterisks indicate the significance differences determined by Student’s t-test (*, 0.01 ≤ P < 0.05; **, P < 0.01). H − J The relative expression comparison of OsAP25, OsAP37 and C6 in the wild-type and osccrl1 anthers. Data are means ± SD (n = 3). Asterisks indicate the significance differences determined by Student’s t-test (*, 0.01 ≤ P < 0.05; **, P < 0.01). K − P Transmission electron micrograph of pollen wall and anther cuticle in the wild type and osccrl1 mutant. Po, pollen; Te, tectum; Ba, bacula; Ne, nexine; In, intine; dPo, defective pollen; dIn, defective intine; dEx, defective exine; E, epidermis; C, cuticle; dC, defective cuticle. Scale bars, 1 μm in (k, m), 0.2 μm in (l, n), and 2 μm in (o, p)