Models of embryonic diapause in Carnivora

International Journal of Current Microbiology and Applied Sciences

Biology of Reproduction

Journal of Biological Rhythms, 2018

Bioscientifica Proceedings, 2020

The International Journal of Developmental Biology, 2014

American journal of physiology. Regulatory, integrative and comparative physiology, 2016

Life cycle delays are beneficial for opportunistic species encountering suboptimal environments. Many animals display a programmed arrest of development (diapause) at some stage(s) of their development, and the diapause state may or may not be associated with some degree of metabolic depression. In this review, we will evaluate current advancements in our understanding of the mechanisms responsible for the remarkable phenotype, as well as environmental cues that signal entry and termination of the state. The developmental stage at which diapause occurs dictates and constrains the mechanisms governing diapause. Considerable progress has been made in clarifying proximal mechanisms of metabolic arrest and the signaling pathways like insulin/Foxo that control gene expression patterns. Overlapping themes are also seen in mechanisms that control cell cycle arrest. Evidence is emerging for epigenetic contributions to diapause regulation via small RNAs in nematodes, crustaceans, insects, an...

Biology of reproduction, 2016

Embryonic diapause is an evolutionary strategy to ensure that offspring are born when maternal and environmental conditions are optimal for survival. In many species of carnivores, obligate embryonic diapause occurs in every gestation. Reciprocal embryo transplant studies indicate that embryo arrest during diapause is conferred by uterine conditions and is due to a lack of specific factors necessary for continued development. In previous studies, global gene expression analysis revealed reduced uterine expression during diapause of a cluster of genes in the mink that regulate the abundance of polyamines, including ornithine decarboxylase 1 (ODC1). In addition, in vivo inhibition of the conversion of ornithine to the polyamine, putrescine, induced a reversible arrest in mink embryonic development and an arrest in trophoblast cell proliferation in vitro. Previous studies have implicated prolactin as the principal endocrine signal to terminate diapause. In this study, uterine expressio...

Animal Reproduction Science, 2000

Respond Working Paper Series, 2020

This report analyses and interrogates the accountability and transparency regime of the European Union’s border agency Frontex. Frontex was established as a European Union agency in the field of border, migration and asylum policies in 2004 and began operating in 2005. Over the last 15 years, the mandate of the agency, originally tasked with coordinating the operational management of the European Union’s external border through support to the EU’s member states, has expanded significantly. Through a series of reforms, most notably in 2007, and 2016 and 2019, the agency has become a pivotal actor in what is referred to as ‘European Integrated Border Management’. Since the creation of the agency and its first operations, there has been significant concern, both from the European Parliament as well as NGOs and other civil society organisations that the executive mandate of the agency has not been counterbalanced by effective mechanisms for accountability, particularly with respect to fundamental rights. To an extent, the Frontex monitoring and accountability regime has improved since 2011 through legislative change, thus strengthening the above mechanisms. The findings of the report however show that despite the continued expansion and strengthening of monitoring and accountability mechanisms since 2016, these efforts have again not resulted in an effective system for monitoring, investigating, addressing, and preventing fundamental rights violations at Europe’s external borders.