The plasmid PSP109-E8 containing CAO was transformed into Chlamydomonas cbn1-48 mt+ mutant strian by electroporation.And the recovery expression of the chlorophyll b was detected in transformants

the result indicated that the mutant genes cbn1 and cao which both lost the ability of chlorophyll b synthesis have allelic characters;1641-1b(cbn1-43 mt+)and CC-1354(cbn1-48 mt+) mutant strains were taken mating with the CBS5-c1

CBS5c5 segregants of mutant strain cao5 mt-

then obtained 1 842 meiotic segregants by cell mating random analysis and wild type segregants were not detected

the result confirmed that mutant genes cbn1 and cao was close linkage;50 segregants were obtained by cell mating tetrat analysis and wild type segregants were also not detected

the result further indicated that the mutant genes cbn1 and CAO have allelic characters;According to CAO sequence

were probes were designsed relating to 5′-end and 3′-end of CAO

DNA dot blot was carried out to use above two probes with 21 BAC clones between two molecular marker GBP1 and RB47 on chlamydomonas linkagegroupⅠ

positive spot was detected in hybridization of 33e2 BAC clone with both two probes

the result indicated the position of the CAO on the molecular map was on the 33e2 BAC clone which located between GBP1 and RB47.