Premium
Gametogenesis, Fertilization and Ookinete Differentiation of Leucocytozoon smithi
Author(s) -
STEELE EDNA JOSEF,
NOBLET GAYLE PITTMAN
Publication year - 2001
Publication title -
journal of eukaryotic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.067
H-Index - 77
eISSN - 1550-7408
pISSN - 1066-5234
DOI - 10.1111/j.1550-7408.2001.tb00423.x
Subject(s) - biology , microbiology and biotechnology , zygote , cytoplasm , gametogenesis , axoneme , gametocyte , microtubule , genetics , embryo , immunology , embryogenesis , flagellum , malaria , gene , plasmodium falciparum
. Development of Leucocytozoon smithi during gametogenesis, fertilization, and ookinete differentiation was studied by light and electron microscopy. Gametogenesis occurred rapidly, within 1–2 min after gametocytes were ingested by black flies. Usually one axoneme, but not infrequently two, was observed in microgametes. The macrogamete nucleus was characteristically elongated and fragmented, with a convoluted nuclear envelope. Fertilization occurred within five min after ingestion of gametocytes by the vector. The entire axoneme and nucleus of the microgamete entered the cytoplasm of the macrogamete. Zygote differentiation resembled sporozoite formation in that a thickened inner membrane and subpellicular microtubules developed beneath the plasmalemma, followed by cytoplasmic protrusion or evagination to form the anterior end. Extension of the inner thickened membrane continued as the xygote elongated. Development of sausage‐shaped ookinetes was completed within 6–8 h after ingestion of a blood meal by a black fly. Mature ookinetes possessed a single nucleus, double‐layered pellicle, canopy, apical pore, polar ring complex, subpellicular microtubules, micronemes, crystalloids, abundant mitochondria, endoplasmic reticulum, and ribosomes. Comparison of development of L. smithi with species of Plasmodium and Haemoproteus revealed general similarities in both sexual and asexual development within the insect vector. A diagram summarizing life cycle events for L. smithi is included.