In vivo Chlase activity of CORI1 in wild-type, coi1, and transgenic plants. A, PCR products of genomic DNA extracted from Arabidopsis plants transformed with sense (wtS and coi1S) and antisense (wtA1) constructs of 35S::ATHCOR1, showing the amplification of DNA fragments of approximately 800 bp specific to the transgenes (arrowhead); pBI, control vector containing 35S::ATHCOR1 used for transformation of sense plants; M, 1-kb Mr ladder. B, Northern-blot analysis of total RNA extracted from leaves of wild type (wt), coi1 mutant, and two individuals of each transgenic line expressing the sense or antisense ATHCOR1, probed with ATHCOR1 or ubiquitin (below). An mRNA sample from wounded leaves of wild-type plants as positive control for ATHCOR1 induction is shown (W), and the arrowhead indicates the expected approximately 1.3-kb band; antisense plants showed a major approximately 1-kb band (arrow) plus smaller bands also observed in wtS4 and COI1/coi1S2, an F1 plant from the cross between wild type and homozygous coi1 transformed with the sense construct. C, Hexane/acetone partitioning of the Chl (top phase) and Chlide (acetone phase) extracted from leaves of wild-type, coi1 mutant, and transgenic plants.