期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1999
卷号：96
期号：22
页码：12577-12582
DOI：10.1073/pnas.96.22.12577
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The non-Mendelian inheritance of organelle genes is a phenomenon common to almost all eukaryotes, and in the isogamous alga Chlamydomonas reinhardtii, chloroplast (cp) genes are transmitted from the mating type positive (mt+) parent. In this study, the preferential disappearance of the fluorescent cp nucleoids of the mating type negative (mt-) parent was observed in living young zygotes. To study the change in cpDNA molecules during the preferential disappearance, the cpDNA of mt+ or mt- origin was labeled separately with bacterial aadA gene sequences. Then, a single zygote with or without cp nucleoids was isolated under direct observation by using optical tweezers and investigated by nested PCR analysis of the aadA sequences. This demonstrated that cpDNA molecules are digested completely during the preferential disappearance of mt- cp nucleoids within 10 min, whereas mt+ cpDNA and mitochondrial DNA are protected from the digestion. These results indicate that the non-Mendelian transmission pattern of organelle genes is determined immediately after zygote formation.
