Germ cell differentiation in reverse-sexed reproductive organs and interspecies germ line chimeras provides insight into the mechanism of germ cell development and represents a useful tool for conservation of endangered birds. We investigated the migration and survival capacity of male chicken primordial germ cells (PGCs) in female chicken embryos and in quail and Korean ring-necked pheasant em...

We identified MRG-1, a Caenorhabditis elegans chromodomain-containing protein that is similar to the human mortality factor-related gene 15 product (MRG15). RNA-mediated interference (RNAi) of mrg-1 resulted in complete absence of the germline in both hermaphrodite and male adults. Examination of the expression of PGL-1, a component of P granules, revealed that two primordial germ cells (PGCs) ...

In mammals, the development of pluripotency and specification of primordial germ cells (PGCs) have been studied predominantly using mice as a model organism. However, divergences among mammalian species for such processes have begun to be recognized. Between humans and mice, pre-implantation development appears relatively similar, but the manner and morphology of post-implantation development a...

Chicken embryo manipulation, especially germline manipulation, recently has progressed greatly by devising important experimental techniques, such as embryo culture and primordial germ cell (PGC) manipulation. Embryogenesis and embryonic development in chickens are affected by gravity at various developmental stages. Freshly collected PGC population seems to contain germline-competent PGCs in o...

AIM To assess whether exogenous estradiol has any effect on migration of primordial germ cells (PGCs) in the chick. METHODS Fertilized eggs were treated with 17beta-estradiol (E(2)) (80 microg/egg) at stage X (day 0 of incubation), stages 8-10 (incubation 30 h) and 13-15 (incubation 55 h). Controls received vehicle (emulsion) only. Changes in PGC number were measured on different days accordi...

The present study was conducted to investigate the effects of ovarian morphology on oocyte quantity and quality, as well as the effect of preincubated granulosa cells (PGCs) on in vitro maturation of buffalo oocytes and steroid hormone production. A total of 52 ovarian pairs were grouped into 3 types: Type I (with functional corpus luteum), Type II (with regressed corpus luteum), or Type III (w...

Human embryonic germ cells (EGCs) provide a powerful model for identifying molecules involved in the pluripotent state when compared to their progenitors, primordial germ cells (PGCs), and other pluripotent stem cells. Microarray and Principal Component Analysis (PCA) reveals for the first time that human EGCs possess a transcription profile distinct from PGCs and other pluripotent stem cells. ...

BACKGROUND MicroRNAs (miRNAs) are critical regulators of transcriptional and post-transcriptional gene silencing, which are involved in multiple developmental processes in many organisms. Apart from miRNAs, mouse germ cells express another type of small RNA, piwi-interacting RNAs (piRNAs). Although it has been clear that piRNAs play a role in repression of retrotransposons during spermatogenesi...

A hallmark of germline cells throughout the animal kingdom is their ability to execute meiosis. However, despite its prime importance, little is known about how germline progenitors acquire this ability. In Drosophila, the primordial germ cells (PGCs) are characterized by the inheritance of germ plasm, which contains maternal factors that have sufficient ability to direct germline development. ...

An important mechanism for the specification and development of the animal germ line is the localization of specific molecules to the germ plasm. Restriction of these molecules to the germ line is considered to be critical for proper development of the germ line as well as the soma. Cytoplasmic localization alone, however, may not be sufficient to achieve germ line-specific expression. While ze...