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991.
992.
The disulfide contents of human sperm heads, as measured by reduction to the sulfhydryls and subsequent alkylation with 14C-iodoacetamide, increase about 2-fold during the sperm passage from the caput to caudal epididymides. Majority of the increased disulfides resides in the human protamine fractions. 相似文献
993.
A polycystic kidney-disease gene homologue required for male mating behaviour in C. elegans. 总被引:6,自引:0,他引:6
The stereotyped mating behaviour of the Caenorhabditis elegans male is made up of several substeps: response, backing, turning, vulva location, spicule insertion and sperm transfer. The complexity of this behaviour is reflected in the sexually dimorphic anatomy and nervous system. Behavioural functions have been assigned to most of the male-specific sensory neurons by means of cell ablations; for example, the hook sensory neurons HOA and HOB are specifically required for vulva location. We have investigated how sensory perception of the hermaphrodite by the C. elegans male controls mating behaviours. Here we identify a gene, lov-1 (for location of vulva), that is required for two male sensory behaviours: response and vulva location. lov-1 encodes a putative membrane protein with a mucin-like, serine-threonine-rich amino terminus followed by two blocks of homology to human polycystins, products of the autosomal dominant polycystic kidney-disease loci PKD1 and PKD2. LOV-1 is the closest C. elegans homologue of PKD1. lov-1 is expressed in adult males in sensory neurons of the rays, hook and head, which mediate response, vulva location, and potentially chemotaxis to hermaphrodites, respectively. PKD-2, the C. elegans homologue of PKD2, is localized to the same neurons as LOV-1, suggesting that they function in the same pathway. 相似文献
994.
The immunoperoxidase technique has clearly demonstrated that SV 40 T antigen is dissociated from the chromosomes in mitotic cells, and massive transport of T antigen from the cytoplasm to the nucleus appears to take place during or immediately after the telophase. 相似文献
995.
996.
Orconectes virilis (northern crayfish) were collected from 67 sites in Alberta, Saskatchewan, Manitoba, and far-western Ontario, Canada, and yielded 2 species of branchiobdellidans, Cambarincola vitreus and Cambarincola chirocephalus. This is the first report of branchiobdellidans in the Prairie Provinces. Cambarincola vitreus was distributed across the study area, but C. chirocephalus appeared to be restricted to southeastern Saskatchewan, southern Manitoba, and the site in western Ontario. Neither branchiobdellidan species was observed on crayfish in the Beaver River or the South Saskatchewan River and associated tributaries upstream (west) of Saskatoon, Saskatchewan, despite multiple sampling at these locations. 相似文献
997.
Vivek S. Peche Tad A. Holak Bhagyashri D. Burgute Kosmas Kosmas Sushant P. Kale F. Thomas Wunderlich Fatiha Elhamine Robert Stehle Gabriele Pfitzer Klaus Nohroudi Klaus Addicks Florian Stöckigt Jan W. Schrickel Julia Gallinger Michael Schleicher Angelika A. Noegel 《Cellular and molecular life sciences : CMLS》2013,70(3):527-543
Cyclase-associated proteins are highly conserved proteins that have a role in the regulation of actin dynamics. Higher eukaryotes have two isoforms, CAP1 and CAP2. To study the in vivo function of CAP2, we generated mice in which the CAP2 gene was inactivated by a gene-trap approach. Mutant mice showed a decrease in body weight and had a decreased survival rate. Further, they developed a severe cardiac defect marked by dilated cardiomyopathy (DCM) associated with drastic reduction in basal heart rate and prolongations in atrial and ventricular conduction times. Moreover, CAP2-deficient myofibrils exhibited reduced cooperativity of calcium-regulated force development. At the microscopic level, we observed disarrayed sarcomeres with development of fibrosis. We analyzed CAP2’s role in actin assembly and found that it sequesters G-actin and efficiently fragments filaments. This activity resides completely in its WASP homology domain. Thus CAP2 is an essential component of the myocardial sarcomere and is essential for physiological functioning of the cardiac system, and a deficiency leads to DCM and various cardiac defects. 相似文献
998.
The seven species of Clinohelea known to inhabit North America are described and illustrated, and a key is provided for identification. Two species groups are recognized: the unimaculata group and the bimaculata group. Clinohelea longitheca and C. pseudonubifera are new. Clino - helea nebulosa (Malloch) is a synonym of C. curriei (Coquillett) NEW SYNONOMY. 相似文献
999.
1000.