Analysis apaptosis phenomena of nuclei in zygospores of Phycomyces

藻类接合孢子细胞核凋亡现象分析

• 批准号: 10640645
• 负责人: OOTAKI Tamotsu
• 金额: $ 2.11万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10640645/
• 关键词: Phycomyces; Meiosis; Mating; Zygospore; Karyogamy; 菌糸の再生

Phycomyces is multinucleate and thousands of nuclei transfer from parental gametangia into zygospores when two mating types were mated. Only one or two diploid nuclei, however, are able to survive until the end of the dormancy period of about 6 months. The other remained nuclei lose their functions and gradually disappear with an increase in the age of zygospores. To explore the mechanisms of this apaptosis phenomenon of nuclei, the zygospores were inspected for the age-dependent changes of their characteristics.1. The zygospores increased in their physical hardness after the 10th day of the mating, about 5 times harder than the zygospores before 10 days after mating. The hardness recovered to the normal just before the zygospore germination. Emergence of a large central oil-drop is another characteristic of the post-10th-day zygospores. The oil drop also disappeared before the germination.2. Genetic analyses of nuclei in the spores developed on sporangiophores and hyphae which regener … More ated from the incised zygospores with different ages revealed that meiosis has not completed before 10th day after mating. No regeneration of any structures occurred on the post-10th day zygospores.3. The zygospores formed between the heterokaryotic parents with several different genetic markers were selected and their protoplasm including nuclei were transferred into the sporangiophore segments of an auxotropic mutant. The spore analysis for recombination of genetic markers of the regenerants on the sporangiophore segments implied that meiosis occurred in the zygospores around 30th day after the mating.4. Microscopic and electromicroscopic observations revealed that the nuclei increased in their volumes at the 7-8th days after mating but sharply decreased after the 10th day till the 20th day.5. Aggregation of some degenerated nuclei was found in the aged zygospores after the 30th day. Nuclei with broken membrane were also found. These findings imply that all the nuclei except for the survive diploid nucleus(ei) lose their functions 10 days after mating. Less

藻囊是多核的，当两种交配类型交配时，成千上万的核从亲本配子囊转移到接合孢子中。然而，只有一个或两个二倍体细胞核能够存活到大约6个月的休眠期结束。其余的核随着接合孢子年龄的增长逐渐丧失功能而消失。为了探讨核的这种凋亡现象的机制，我们观察了接合孢子的特征随年龄的变化.接合孢子的物理硬度在交配后第10天增加，约为交配后10天前接合孢子的5倍。在接合孢子萌发前硬度恢复正常。出现一个大的中央油滴是第10天后的接合孢子的另一个特征。油滴也在萌发前消失.孢子囊梗上发育的孢子和再生的菌丝中细胞核的遗传分析 ...更多信息 对不同年龄的接合孢子进行减数分裂的观察表明，交配后10天内减数分裂尚未完成。第10天后合子孢子没有任何结构的再生.选择具有几个不同遗传标记的异源亲本之间形成的接合孢子，并将其原生质（包括细胞核）转移到营养缺陷型突变体的孢子囊柄片段中。对再生子的孢子囊梗上遗传标记的重组进行孢子分析，结果表明接合孢子在交配后30 d左右发生减数分裂.光镜和电镜观察显示，交配后7- 8天，核体积增大，交配后10 ~ 20天，核体积急剧减小.老化的接合孢子在第30天以后出现部分退化核的聚集现象。这些结果表明，在交配后10天，除存活的二倍体细胞核（ei）外，其余细胞核均丧失了功能。少

项目成果

Horie, Tadashi: "Developmental stage-dependent response of Pilobolus crystallinus sporangiophores to gravitative and centrifugal stimuli"Mycoscience. 39. 463-470 (1998)

Horie，Tadashi：“结晶毛球菌孢子梗对重力和离心刺激的发育阶段依赖性反应”Mycoscience。

Tadashi Horie: "Developmental stage-dependent response of Pilobolus crystallinus sporangiophores to gravitative and centrifugal stimuli"Mycoscience. 39. 463-470 (1998)

Tadashi Horie：“结晶毛球菌孢子梗对重力和离心刺激的发育阶段依赖性反应”Mycoscience。

Schimek,Christine: "Gravitropism in phycomyces : a role for sedimenting protein crystals and floating lipid globules"Planta. 210. 132-142 (1999)

Schimek，Christine：“藻菌的向地性：沉淀蛋白质晶体和漂浮脂质球的作用”Planta。

Schimek, Christine: "Gravitropism in Phycomyces : a role for sedimenting protein crystals and floating lipid globules"Planta. 210. 132-142 (1999)

Schimek，Christine：“须霉菌的向地性：沉淀蛋白质晶体和漂浮脂质球的作用”Planta。

Christine Schimek: "Protein crystals in Phycomyces sporangiophores are involved in graviperception"Advanced Space Research. 24. 687-696 (1999)

克里斯汀·希梅克 (Christine Schimek)：“孢子梗藻中的蛋白质晶体参与重力感知”高级空间研究。