tailieunhanh - báo cáo khoa học: " Nickel and low CO2-controlled motility in Chlamydomonas through complementation of a paralyzed flagella mutant with chemically regulated promoters"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Nickel and low CO2-controlled motility in Chlamydomonas through complementation of a paralyzed flagella mutant with chemically regulated promoters | Ferrante et al. BMC Plant Biology 2011 11 22 http 1471-2229 11 22 BMC Plant Biology RESEARCH ARTICLE Open Access Nickel and low CO2-controlled motility in Chlamydomonas through complementation of a paralyzed flagella mutant with chemically regulated promoters Paola Ferrante1 Dennis R Diener2 Joel L Rosenbaum2 Giovanni Giuliano1 Abstract Background Chlamydomonas reinhardtii is a model system for the biology of unicellular green algae. Chemically regulated promoters such as the nickel-inducible CYC6 or the low CO2-inducible CAH1 promoter may prove useful for expressing at precise times during its cell cycle proteins with relevant biological functions or complementing mutants in genes encoding such proteins. To this date this has not been reported for the above promoters. Results We fused the CYC6 and CAH1 promoters to an HA-tagged RSP3 gene encoding a protein of the flagellar radial spoke complex. The constructs were used for chemically regulated complementation of the pf14 mutant carrying an ochre mutation in the RSP3 gene. 7 to 8 of the transformants showed cells with restored motility after induction with nickel or transfer to low CO2 conditions but not in non-inducing conditions. Maximum complementation 5 motile cells was reached with very different kinetics 5-6 hours for CAH1 48 hours for CYC6 . The two inducible promoters drive much lower levels of RSP3 protein expression than the constitutive PSAD promoter which shows almost complete rescue of motility. Conclusions To our knowledge this is the first example of the use of the CYC6 or CAH1 promoters to perform a chemically regulated complementation of a Chlamydomonas mutant. Based on our data the CYC6 and CAH1 promoters should be capable of fully complementing mutants in genes whose products exert their biological activity at low concentrations. Background Chlamydomonas reinhardtii is a unicellular green alga capable of both photosynthetic and fermentative growth. A plethora of mutants in .