identification and characterization of lhcb1 co-suppressed line in arabidopsis

to explore the function of light-harvesting complex protein (lhcp) in arabidopsis growth and development, the leclere and bartel seed collection was screened. in this collection randomly cloned cdnas are expressed under the camv35s promoter. a pale green line has been identified and characterized in more details. analysis of the inserted cdna in the pale green line showed it encodes lhcb1 proteins. the transcript level of lhcb1 in the selected line was less than that of the wild type (wt) arabidopsis plant. characterization of the lhcb1 co-suppressed line was achieved through its comparison with the wt plants when both were grown under normal irradiance. then several measurements were performed such as: fresh and dry weight, chla, chlb, chla/b ratios and total chlorophyll content, soluble and insoluble sugar contents, total protein level, hill reaction level and chlorophyll fluorescence. the lhcb1co-suppressed plants showed smaller leaf area with pale green coloration. suppression of the lhcb1 gene significantly reduced fresh weight, chla, chlb content, total chlorophyll, and the rate of hill reaction. soluble and insoluble sugars, total protein, and chlorophyll fluorescence did not show significant differences between this line and wt plants. meanwhile there was not any significant difference in fluorescence parameters between the wt and lhcb1 co-suppressed line.