CAJ | 학술논문

从超微结构水平上对葫芦藓(Funaria hygrometrica Hedw.)精子发生过程中胞间连接系统的结构及其变化动态进行了研究.结果表明,同一区中的相邻生精细胞由大量胞质桥相连,而不同区的细胞之间则不存在胞质桥.胞间连丝存在于套细胞之间以及套细胞与生精细胞之间,但它在生精细胞间不存在.在精子器发生的后期,当精子细胞壁开始降解时,同一个精子器中所有的精子细胞似乎都由扩大的胞质桥相互连接.胞质桥一直保持到精子分化的后期,最终精子细胞同步分化成精子.胞间连丝与胞质桥具有不同的内部结、分布以及生物发生机制,这表明它们在精子器的发育过程中可能扮演着不同的角色.
종초미결구수평상대호호선(Funaria hygrometrica Hedw.)정자발생과정중포간련접계통적결구급기변화동태진행료연구.결과표명,동일구중적상린생정세포유대량포질교상련,이불동구적세포지간칙불존재포질교.포간련사존재우투세포지간이급투세포여생정세포지간,단타재생정세포간불존재.재정자기발생적후기,당정자세포벽개시강해시,동일개정자기중소유적정자세포사호도유확대적포질교상호련접.포질교일직보지도정자분화적후기,최종정자세포동보분화성정자.포간련사여포질교구유불동적내부결、분포이급생물발생궤제,저표명타문재정자기적발육과정중가능분연착불동적각색.
Cytoplasmic bridge, as a broader cellular connection structure, exists in plants from Volvoxto higher plants, but has been subjected to less investigation as compared to plasmodesmata. It has been speculated that the structure may be related to the synchronization of cell division and development during the microsporegenesis and spermatogenesis. During spermatogenesis in bryophytes, the spermatogenous cells are divided into several domains within an antheridium, and their divisions are synchronous. However, their cellular connection system has not been investigated systematically. In this study, we undertook an ultrastructural examination of the structure and dynamics of the intercellular connection system during the spermatogenesis in Funaria hygrometrica Hedw. The result revealed that within each individual domain, synchronously dividing spermatogenous cells were connected with each other by numerous cytoplasmic bridges, which were absent in the walls between different domains. The plasmodesmata connected spermatogenous cells with the cells of jacket layer, and also existed between the jacket layer cells, but absent in the walls between the developing spermatogenous cells. At the late stage of the antheridial development, as the cell wall began to degrade, all of the spermatid cells within an antheridium seem connected with each other by the expanded cytoplasmic bridges. The cytoplasmic bridges retained to the late stage of spermatid's differentiation, and finally, the spermatids synchronously differentiated into spermatozoids. The different internal structures, biogenesis mechanisms and distribution between the plasmodesmata and cytoplasmic bridges suggest that they may play distinct roles during the development of antheridia.