In an effort to contribute to the development of Xenopus tropicalis as an amphibian model system, we carried out a detailed histological analysis of the process of gonadal sex differentiation and were able to find evidence that gonadal differentiation in X. tropicalis follows an antero-posterior gradient. Although the main reason for the presence of a gradient of sex differentiation is still unknown, this gradient enabled us to define the early events that signal ovarian and testicular differentiation and to identify the undifferentiated gonad structure. Given the various advantages of this emerging model, our work paves the way for experiments that should contribute to our understanding of the dynamics and mechanisms of gonadal sex differentiation in amphibians.
Institute for the Advanced Study of Human Biology, Kyoto University Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University Center for iPS Cell Research and Application, Kyoto University.
The germ-cell lineage ensures the creation of new individuals, perpetuating/diversifying the genetic and epigenetic information across the generations. We have been investigating the mechanism for germ-cell development, and have shown that mouse embryonic stem cells (mESCs)/induced pluripotent stem cells (miPSCs) are induced into primordial germ cell-like cells (mPGCLCs) with a robust capacity both for spermatogenesis and oogenesis and for contributing to offspring. These works have served as a basis for elucidating key mechanisms during germ-cell development such as epigenetic reprogramming, sex determination, meiotic entry, and nucleome programming.
Chameleons are a family of lizards distinguished by several unique features related to their arboreal lifestyles, such as a ballistic tongue, skin color changes, independent movement of both eyes, a prehensile tail, and cleft hands and feet. The veiled chameleon (Chamaeleo calyptratus) has been proposed as a promising model species for studying squamate biology. Despite its potential, the developmental biology of this species remains poorly understood, particularly in terms of gonadal development.
Background: Muscle stem cells (MuSCs) undergo numerous state transitions throughout life, which are critical for supporting normal muscle growth and regeneration. Epigenetic modifications in skeletal muscle play a significant role in influencing the niche and cellular states of MuSCs. Mixed-lineage leukemia 4 (Mll4) is a histone methyltransferase critical for activating the transcription of various target genes and is highly expressed in skeletal muscle.
Background: The systemic inflammatory response index (SIRI) is calculated via the following formula: SIRI = monocyte count × neutrophil count/lymphocyte count. The value of the SIRI in predicting the prognosis of gastric cancer (GC) remains controversial. This study revealed the precise effect of the SIRI in predicting GC prognosis through a meta-analysis.
