Zebrafish akt2 is essential for survival, growth, bone development, and glucose homeostasis
Publication date: Available online 26 January 2017 Source:Mechanisms of Development Author(s): Dawei Zhang, Jing Wang, Chi Zhou, Wuhan Xiao As one of three akt isoforms, akt2 plays a key role in the regulation of widely divergent cellular processes in mammals. However, its role and underlying mechanisms in zebrafish remain largely unknown. To elucidate the function of akt2 in zebrafish, we generated zebrafish lacking akt2 gene via CRISPR/Cas9 technology. Akt2-null zebrafish exhibit partial lethality and severe growth deficiency, which is different from those observed in akt2-null mice. Furthermore, akt2-null zebrafis...
Source: Mechanisms of Development - January 26, 2017 Category: Biology Source Type: research
Corrigendum to “Regulation of Polycomb group genes Psc and Su(z)2 in Drosophila melanogaster” [Mech. Dev. 128 (2012) 536–547]
Publication date: Available online 18 January 2017 Source:Mechanisms of Development Author(s): Sung Yeon Park, Yuri B. Schwartz, Tatyana G. Kahn, Dalal Asker, Vincenzo Pirrotta (Source: Mechanisms of Development)
Source: Mechanisms of Development - January 18, 2017 Category: Biology Source Type: research
Developmental tracing of oocyte development in gonadal soma-derived factor deficiency medaka (Oryzias latipes) using a transgenic approach
Publication date: Available online 16 January 2017 Source:Mechanisms of Development Author(s): Guijun Guan, Kaiqing Sun, Xi Zhang, Xiaomiao Zha, Mingyou Li, Yan Yan, Yunzhi Wang, Jianbin Chen, Meisheng Yi, Yunhan Hong Gonadal soma-derived factor (gsdf) is reported to be a male initiator in medaka based on loss- and gain- of function via targeted disruption, or transgenic over-expression. However, little is known about how gsdf promotes undifferentiated gonad entry into male pathways or prevents entry into the female pathway. We utilized a visible folliculogenesis system with a reporter cassette of dual-color fl...
Source: Mechanisms of Development - January 16, 2017 Category: Biology Source Type: research
Identification of the Doublesex protein binding sites that activate expression of lozenge in the female genital disc in Drosophila melanogaster
In this study, we found two sequences (lz-DBS1 and lz-DBS2) within lz locus that showed high homoloty to the DSX binding motif identified previously. Competition assays using recombinant DSX DNA-binding domain (DSX-DBD) protein verified that the DSX-DBD protein bound to lz-DBS1 and lz-DBS2 in a sequence-specific manner with lower affinity than to the known DSX binding site in the bric-à-brac 1 (bab1) gene. Reporter gene analyses revealed that a 2.5-kbp lz genomic fragment containing lz-DBS1 and lz-DBS2 drove reporter gene (EGFP) expression in a manner similar to endogenous lz expression in the female genital disc. Mutatio...
Source: Mechanisms of Development - January 10, 2017 Category: Biology Source Type: research
Wnt signaling balances specification of the cardiac and pharyngeal muscle fields
Publication date: Available online 10 January 2017 Source:Mechanisms of Development Author(s): Amrita Mandal, Andrew Holowiecki, Yuntao Charlie Song, Joshua S. Waxman Canonical Wnt/β-catenin (Wnt) signaling plays multiple conserved roles during fate specification of cardiac progenitors in developing vertebrate embryos. Although lineage analysis in ascidians and mice has indicated there is a close relationship between the cardiac second heart field (SHF) and pharyngeal muscle (PM) progenitors, the signals underlying directional fate decisions of the cells within the cardio-pharyngeal muscle field in vertebrates are n...
Source: Mechanisms of Development - January 10, 2017 Category: Biology Source Type: research
Drosophila dorsal closure: An orchestra of forces to zip shut the embryo
Publication date: Available online 7 January 2017 Source:Mechanisms of Development Author(s): Peran Hayes, Jérôme Solon Dorsal closure, a late-embryogenesis process, consists in the sealing of an epidermal gap on the dorsal side of the Drosophila embryo. Because of its similarities with wound healing and neural tube closure in humans, it has been extensively studied in the last twenty years. The process requires the coordination of several force generating mechanisms, that together will zip shut the epidermis. Recent works have provided a precise description of the cellular behavior at the origin of these forces and ...
Source: Mechanisms of Development - January 7, 2017 Category: Biology Source Type: research
MicroRNA-224 delays oocyte maturation through targeting Ptx3 in cumulus cells
In this study, we aimed to clarify microRNA-224′s (miR-224) role in cumulus cells (CCs), to find out whether a change level of miR-224 in CCs could influence the maturation of oocyte. We found that overexpression of miR-224 of CCs led to the impairment of cell expansion, along with a decrease in the gene expression associated with cell expansion and maturation of oocyte. The increased expression of miR-224 in CC interrupted oocyte cell cycle at the GV stage. The GDF9, BMP15 and ZP3 of the oocytes were also down-regulated. The following in vitro fertilization had yielded a lower number of oocytes from cumulus-oocyte compl...
Source: Mechanisms of Development - December 28, 2016 Category: Biology Source Type: research
Forces directing germ-band extension in Drosophila embryos
Publication date: Available online 22 December 2016 Source:Mechanisms of Development Author(s): Deqing Kong, Fred Wolf, Jörg Großhans Body axis elongation by convergent extension is a conserved developmental process found in all metazoans. Drosophila embryonic germ-band extension is an important morphogenetic process during embryogenesis, by which the length of the germ-band is more than doubled along the anterior-posterior axis. This lengthening is achieved by typical convergent extension, i.e. narrowing the lateral epidermis along the dorsal-ventral axis and simultaneous extension along the anterior-posterior axis...
Source: Mechanisms of Development - December 22, 2016 Category: Biology Source Type: research
piragua encodes a zinc finger protein required for development in Drosophila
Publication date: Available online 21 December 2016 Source:Mechanisms of Development Author(s): Nestor O. Nazario-Yepiz, Juan R. Riesgo-Escovar We isolated and characterized embryonic lethal mutations in piragua (prg). The prg locus encodes a protein with an amino terminus Zinc Finger-Associated-Domain (ZAD) and nine C2H2 zinc fingers (ZF). prg mRNA and protein expression during embryogenesis is dynamic with widespread maternal contribution, and subsequent expression in epithelial precursors. About a quarter of prg mutant embryos do not develop cuticle, and from those that do a small fraction have cuticular defects. Ro...
Source: Mechanisms of Development - December 21, 2016 Category: Biology Source Type: research
Mechanisms of retinoic acid signaling during cardiogenesis
Publication date: Available online 19 December 2016 Source:Mechanisms of Development Author(s): Sonia Stefanovic, Stéphane Zaffran Substantial experimental and epidemiological data have highlighted the interplay between nutritional and genetic factors in the development of congenital heart defects. Retinoic acid (RA), a derivative of vitamin A, plays a key role during vertebrate development including the formation of the heart. Retinoids bind to RA and retinoid X receptors (RARs and RXRs) which then regulate tissue-specific genes. Here, we will focus on the roles of RA signaling and receptors in gene regulation during...
Source: Mechanisms of Development - December 19, 2016 Category: Biology Source Type: research
Tension (re)builds: Biophysical mechanisms of embryonic wound repair
Publication date: Available online 15 December 2016 Source:Mechanisms of Development Author(s): Teresa Zulueta-Coarasa, Rodrigo Fernandez-Gonzalez Embryonic tissues display an outstanding ability to rapidly repair wounds. Epithelia, in particular, serve as protective layers that line internal organs and form the skin. Thus, maintenance of epithelial integrity is of utmost importance for animal survival, particularly at embryonic stages, when an immune system has not yet fully developed. Rapid embryonic repair of epithelial tissues is conserved across species, and involves the collective migration of the cells around th...
Source: Mechanisms of Development - December 15, 2016 Category: Biology Source Type: research
Hoxa1 and Hoxb1 are required for pharyngeal arch artery development
Publication date: Available online 10 December 2016 Source:Mechanisms of Development Author(s): Marine Roux, Brigitte Laforest, Nathalie Eudes, Nicolas Bertrand, Sonia Stefanovic, Stéphane Zaffran Hox transcription factors play critical roles during early vertebrate development. Previous studies have revealed an overlapping function of Hoxa1 and Hoxb1 during specification of the rhombomeres from which neural crest cells emerge. A recent study on Hoxa1 mutant mice documented its function during cardiovascular development, however, the role of Hoxb1 is still unclear. Here we show using single and compound Hoxa1;Hoxb...
Source: Mechanisms of Development - December 9, 2016 Category: Biology Source Type: research
Forces controlling organ growth and size
Publication date: Available online 30 November 2016 Source:Mechanisms of Development Author(s): Dominik Eder, Christof Aegerter, Konrad Basler One of the fundamental questions in developmental biology is what determines the final size and shape of an organ. Recent research strongly emphasizes that besides cell-cell communication, biophysical principals govern organ development. The architecture and mechanics of a tissue guide cellular processes such as movement, growth or differentiation. Furthermore, mechanical cues do not only regulate processes at a cellular level but also provide constant feedback about size and s...
Source: Mechanisms of Development - November 29, 2016 Category: Biology Source Type: research
Mechanical forces during muscle development
Publication date: Available online 29 November 2016 Source:Mechanisms of Development Author(s): Sandra B. Lemke, Frank Schnorrer Muscles are the major force producing tissue in the human body. While certain muscle types specialise in producing maximum forces, others are very enduring. An extreme example is the heart, which continuously beats for the entire life. Despite being specialised, all body muscles share similar contractile mini-machines called sarcomeres that are organised into regular higher order structures called myofibrils. The major sarcomeric components and their organisational principles are conserved th...
Source: Mechanisms of Development - November 28, 2016 Category: Biology Source Type: research
Evolution of the Rax family of developmental transcription factors in vertebrates
Publication date: Available online 10 November 2016 Source:Mechanisms of Development Author(s): Daniela P. Orquera, Flávio S.J. de Souza Rax proteins comprise a small family of paired-type, homeodomain-containing transcription factors with essential functions in eye and forebrain development. While invertebrates possess only one Rax gene, vertebrates can have several Rax paralogue genes, but the evolutionary history of the members of the family has not been studied in detail. Here, we present a thorough analysis of the evolutionary relationships between vertebrate Rax genes and proteins available in diverse genomic da...
Source: Mechanisms of Development - November 9, 2016 Category: Biology Source Type: research
