Abstract
Activation tagging was applied to Arabidopsis green calli to reveal the mechanisms underlying the differentiation of chloroplasts, resulting in screening suppressed greening of calli (sug) mutants which did not green on a modified callus-inducing medium for greening (JSPP meeting, 2009). Four SUG gene candidates were identified by TAIL-PCR and subsequent real-time RT-PCR. The lines in which these SUG genes were over-expressed or knocked out, were obtained. The chlorophyll content in differentiated plants has been reduced at 0.35-0.65 in the over-expression lines in comparison with the wild-type, and it has been enhanced up to 2.06 in a SUG4-knockout line. The over-expression and knockout lines were subjected to analysis of expression of genes for chlorophyll a/b-binding protein (CAB) and small subunit of Rubisco (RBCS). The expression of genes for enzymes involved in chlorophyll biosynthesis is presently examined using GeneChip (Affymetrix).
