we searched for novel chinese hamster ovary (cho) cell mutants defective in peroxisome biogenesis by an improved method using peroxisome targeting sequence (pts) of pex3p (amino acid residues 1–40)-fused enhanced green fluorescent protein (egfp). from mutagenized tkaeg3(1–40) cells, the wild-type cho-k1 stably expressing rat pex2p and of rat pex3p(1–40)-egfp, numerous cell colonies resistant to...

Understanding the mechanisms by which the acrosome reaction is regulated is central to models of fertilization. This article reviews the relationship of the acrosome reaction detected in vitro to sperm function. Proteolytic enzymes in the acrosome digest through the zona pellucida allowing for sperm-oolemma fusion. When this process is impaired, either by lack of an acrosome or acrosomal dysfun...

The sperm of Microstigmus arlei and Microstigmus nigrophthalmus are twisted in a spiral and consist of two regions: the head, formed by an acrosome and a nucleus, and the flagellum, formed by two asymmetric mitochondrial derivatives, a long centriolar adjunct, an axoneme (9+9+2) and two accessory bodies. The head shows a characteristic morphology. The acrosome is very long and is basically made...

The signal transduction pathways involved in the regulation of the acrosome reaction and motility of fowl spermatozoa were investigated. The motility and acrosomal integrity of fowl spermatozoa in TES/NaCl buffer, with or without homogenised inner perivitelline layers (IPVL), prepared from laid fowl eggs, was almost negligible at 40 degrees C. In the presence of 2 mmol CaCl(2)/l at 40 degrees C...

BACKGROUND Endocrine disruptors are exogenous substance, interfere with the endocrine system, and disrupt hormonal functions. However, the effect of endocrine disruptors in different species has not yet been elucidated. Therefore, we investigated the possible effects of 17ß-estradiol (E2), progesterone (P4), genistein (GEN) and 4-tert-octylphenol (OP), on capacitation and the acrosome reaction ...

Cross-linked complexes formed between certain lectins and their specific multivalent carbohydrates and glycoconjugates on the sperm surface were studied for their ability to modify sperm membrane permeability and to induce the acrosome reaction. Wheat germ agglutinin (WGA), concanavalin A (Con A) and peanut agglutinin (PNA) increased the proportions of human spermatozoa permeable to the imperme...

introduction: the acrosome is a sac shaped organelle contaning lysosomal enzyme that is located on the anterior of sperm head. during the acrosome reaction its content is released in the vicinity of the egg. the acrosome reacted sperm then penetrates through the egg barriers. there are several methods for evaluating the acrosomal status; some of those are complex, expensive and/or non-accurate ...

The release of enzymes from the acrosome of the sperm head (acrosome reaction) starts the fertilization process and enables the spermatozoa to penetrate the zona pellucida of the oocytes. Defective acrosome reaction is one of the important causes of infertility in men. To investigate the molecular regulation of spermatogenesis in vivo, we used differential display reverse transcription-polymera...

Platelet activating factor (PAF) is a novel signaling phospholipids that in addition to platelet activation has many biological properties. The acrosome reaction, as an essential step in mammalian fertilization, can occur in response to several agents such as PAF. Therefore, the present study aimed to assess the effect of PAF on the motility and acrosome reaction of ram spermatozoa. Semen was c...

We have previously identified and cloned a human gene, D40, that is preferentially expressed in testis among normal organs, while it is widely expressed in various human tumor cell lines and primary tumors derived from different organs. In this report, we have examined the expression and localization of this protein in human testis with an antibody specific to D40 protein. In Western analyses, ...