摘要:

AbstractTo search the spermatozoa of sea urchins for their lysins, the eggs were inseminated in the presence of various protease inhibitors. Among them, two chymotrypsin‐specific inhibitors, chymostatin and N‐tosyl‐L‐phenylalanyl‐chloro‐methane, as well as p‐nitrophenyl p′‐guanidinobenzoate, inhibit fertilization of the sea urchins, Hemicentrotus pulcherrimus and Strongylocentrotus intermedius.A chymotrypsin‐like protease is presumed to be a lysin of the sea urchins, since the inhibition of fertilization by chymostatin is remarkably diminished if the eggs are pretreated with trypsin or chymotrypsin to break the vitelline coat before insemination, and since N‐tosyl‐L‐phenylalanyl‐chloromethane, and p‐nitrophenyl p′‐guanidinobenzoate, as well as chymostatin, inhibit the fertilization.In all the sea urchins so far studied, elevation of fertilization envelopes is inhibited by leupeptin, antipain, soybean trypsin inhibitor, and p‐nitrophenyl p′‐guanidinobenzoate, all of which are potent trypsin inhibitors.Synthetic inhibitors have cytotoxic side effects on the eggs, but the microbial an

ISSN:0148-7280    

DOI:10.1002/mrd.1120020202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY

摘要:

AbstractImmature rats, aged 27 days, were stimulated to develop preovulatory follicles by subcutaneous injection of 15 IU of pregnant mare serum gonadotrophin (PMSG). Two days later their oocytes were collected. They were cultured under conditions that permitted continuous observation. Times of the initial stages of maturation were carefully noted, in the absence and the presence of 10 μg/ml of bovine luteinizing hormone (LH). LH did not accelerate germinal vesicle disappearance. It was concluded that the immature PMSG‐treated rat was not an appropriate model for the study of LH action; it was speculated that persistence of PMSG mimicked LH in all the oocytes from such dono

ISSN:0148-7280    

DOI:10.1002/mrd.1120020203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY

摘要:

AbstractWhen female Xenopus laevis are injected with [3H]‐vitellogenin or [14C] N‐acetyl glucosamine, most of the labeled material becomes associated three days later with oocytes having a diameter of 0.9–1.1 mm; smaller and larger oocytes are less labeled. With time, the pattern of labeling shifts to larger oocytes, indicating that those oocytes initially labeled continue to grow. We have measured such shifts as a function of time to provide estimates for oocyte growth rates from the end of stage III (diameter = 0.6 mm) to stage VI (diameter = 1.2 mm). The total time required for oocytes to progress through this size increase is 16–24 weeks in unstimulated females and 9–12 weeks in human chorionic gonadotropin (hCG)‐stimulated females. The fastest rate of growth occurs from mid‐stage IV (approximately 0.8 mm diameter) until midstage V (1.2 mm diameter), which corresponds to the period of most pronounced vitellogenin uptake. The relative proportion of oocytes within this size range is also reduced, as predicted under steady‐stage conditions. Evidence is also presented which indicates that the steady‐state level of full‐grown oocytes is maintained by a combination of replenishment and atresia. These results provide the first description of the kinetics of oocyte growth in X laevis females maintained under normal laboratory conditions and should be useful for any considerations of macromolecular events occurri

ISSN:0148-7280    

DOI:10.1002/mrd.1120020204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY

摘要:

AbstractDuring the course of maturation of Xenopus laevis oocyte a burst of phosphorylation occurs around germinal vesicle breakdown. At the same time a relative drop in a unique phosphoprotein (protein I; mot wt ∼40,000) is observed. Enucleation of [32P] labeled oocytes has shown the cytoplasmic localization of protein I. Methylxanthines and cholera toxin, which inhibit progesterone‐induced maturation, block the burst of phosphorylation and do not change the amount or the distribution of [32P] phosphoprote

ISSN:0148-7280    

DOI:10.1002/mrd.1120020205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY

摘要:

AbstractMouse chimaeras produced by aggregation of embryos heterozygous for two different recessive mutations at the T/t complex have been analyzed by breeding to explore the basis for the phenomena of male transmission ratio distortion and sterility associated with these genes. Whereas males of genotypetw2/tw5are always sterile, male chimaeras of the type +/tw2⟷ +/tw5are normally fertile; furthermore, they transmit eachtmutation to the same very high extent seen in ordinary (+/t) heterozygotes. Since spermatogenic cells derived from either the +/tw2and +/tw5genotypes thus function quite independently of one another in mosaic testes, it can be concluded that sterility, and presumably distorted transmission ratio as well, depends on specific interactions between T/t alleles in diploid spermatogenic cells or their individual meiotic descendant

ISSN:0148-7280    

DOI:10.1002/mrd.1120020206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY

摘要:

AbstractDifferences in the exposure of spermatozoa surface components during epididymal passage have been examined using lactoperoxidase‐catalyzed125I‐iodination or labeling with125I‐diazodiiodosulfanilic acid. Labeled surface proteins obtained from caput and cauda epididymides were solubilized in detergent, separated by sodium dodecylsulfate polyacrylamide slab gel electrophoresis, and identified by radiography. Densitometer scans of autoradiograms revealed increased amounts or exposures of surface proteins of ∼35,000, ∼39,000, ∼50,000, and ∼78,000 molecular weight on the cauda epididyma

ISSN:0148-7280    

DOI:10.1002/mrd.1120020207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY

摘要:

AbstractEjaculated spermatozoa from Discoglossus pictus are grouped in bundles, where they are embedded in a network of interwoven threads. Their heads and tails move when exposed to the outermost egg jelly layer, when the bundles are spread across a glass slide or a poly‐L‐lysine‐coated polystyrene tissue culture dish. While moving, single spermatozoa emerge from the bundle and eventually become able to fuse with egg.Spermatozoa were studied by means of immunofluorescent staining, using specific antibodies against actin, myosin, and tubulin, and by means of electron microscopy. Antiactin antibodies stain both the heads and the ridge (which contains the axoneme) of the tail's undulating membrane. Antimyosin antibodies stain the head segment covered by the acrosome cap, and antitubulin antibodies stain the axoneme. The presence of actin and myosin in the spermatozoon head may provide the molecular basis for a cytoskeletal and/or a contractile system which could be involved in the motion sequence as well as subsequent steps of fertiliz

ISSN:0148-7280    

DOI:10.1002/mrd.1120020208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY

摘要:

AbstractAcid nitrophenyl phosphatases from sea urchin eggs and embryos were investigated by gel filtration. Four different forms were found in Hemicentrotus pulcherrimus, and three forms in Anthocidaris crassispina and Pseudocentrotus depressus.The first and second forms (designated AcP‐1 and AcP‐2) had the highest activity in the range of pH 5.6–6.0. The third (designated AcP‐3) had an apparent optimum pH between pH 4.3 and 4.8, and the fourth (designated AcP‐4) showed the maximum activity at pH 3.0. AcP‐1 was much more thermolabile than AcP‐2 and AcP‐3 at 56°C. NaF inhibited AcP‐2, AcP‐3, and AcP‐4 but not AcP‐1. AcP‐1, AcP‐2, and AcP‐3 were observed in the three species, whereas AcP‐4 was not detected in A. crassispina and P. depressus. AcP‐1, AcP‐2, and AcP‐3 were separted by gel filtration.AcP‐1 and AcP‐2 of A. crassispina and H. pulcherrimus were studied in developing embryos. The behavior of these forms in gel filtration changed during development, f

ISSN:0148-7280    

DOI:10.1002/mrd.1120020209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY

摘要:

AbstractZonae pellucidae were collected from bovine ovaries by chopping, dispersing the chopped tissue with collagenase, sieving through nylon mesh screens, and pipetting. The zonae were free of corona cell processes when examined under the scanning electron microscope. Solutions of zonae obtained with collagenase exhibited the same antigenic and sperm receptor properties as those obtained without enzyme treatment.

ISSN:0148-7280    

DOI:10.1002/mrd.1120020210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY

ISSN:0148-7280    

DOI:10.1002/mrd.1120020201

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1979

数据来源: WILEY