Harib Shaqsy

Developmental patterning of the sub-epidermal integument cell layer in Arabidopsis seeds [RESEARCH REPORT]

[ad_1] INTRODUCTION In angiosperms, seed development starts with the double fertilization of the egg and central cell in the ovule that leads to the formation of embryo and endosperm, respectively. Proper seed formation is then achieved through tight spatial and temporal coordination of embryo, endosperm, and seed maternal tissues (Ingram, 2010). In Arabidopsis, ovule primordia are composed of three functional domains: the funiculus, which transports nutrients from the mother plant; the chalaza, which initiates two integuments; and the nucellus, which gives rise to the female gametophyte. Both inner (ii) and outer (oi) integuments are composed of two epidermal cell layers (ii1, ii2, oi1 and oi2) which grow by anticlinal cell divisions to progressively surround the female gametophyte. At the end...

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How the stomach gets its curve [IN THIS ISSUE]

[ad_1] Left-right asymmetry is a common feature of many organs, and is crucial for their function. The stomach is one such organ, with marked curvature on the left compared with the right, resulting in a distinctive shape that is highly conserved among vertebrates. Although it is well established that activation of Nodal controls left-right asymmetry of visceral organs, the cell- and tissue-level morphogenetic mechanisms that drive this phenomenon are poorly understood, especially in the stomach. Now, on p. 1477, Nanette Nascone-Yoder and colleagues shed light on the mechanisms that drive left-right asymmetric development of the stomach in both mouse and Xenopus embryos. The authors start with a gross examination of stomach curvature during development and compare their findings with two...

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A systems-level approach reveals new gene regulatory modules in the developing ear [RESEARCH ARTICLE]

[ad_1] INTRODUCTION In vertebrates, the entire inner ear arises from the otic placode, a simple epithelium next to the hindbrain, which invaginates to form the otic vesicle. The vesicle undergoes extensive morphogenesis, ultimately giving rise to the adult inner ear, an organ of exquisite complexity comprising distinct sensory, non-sensory and neuronal cell types of the auditory and vestibular apparatus. In humans, congenital hearing defects are often due to mutations in developmental genes. Thus, a mechanistic understanding of ear development not only provides insight into the molecular control of ear formation, but could also provide information relevant to the aetiology of human sensory disorders. Specification towards otic fate occurs early in development and requires diverse signals and transcriptional inputs that act...

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