light-sheet-microscopy-imaging-mounting-strategies-for-early

Light Sheet Microscopy Imaging and Mounting Strategies for Early Zebrafish Embryos

Light sheet microscopy has become the methodology of choice for live imaging of zebrafish embryos over long time scales with minimal phototoxicity. In ...

dissection-zebrafish-craniofacial-tissues-upon-staining-with-alcian

Dissection of Zebrafish Craniofacial Tissues Upon Staining with Alcian Blue

Zebrafish, given its optical transparency, is an excellent vertebrate model to study the mechanisms by which craniofacial cartilages form in the embryo. ...

Tata Institute of Fundamental Research

Atypical protein kinase C (aPKC) is a major regulator of cell polarity. Acting in conjunction with Par6, Par3 and the small GTPase Cdc42, aPKC becomes asymmetrically localised and drives the polarisation of cells. aPKC activity is crucial for its own asymmetric localisation, suggesting a hitherto unknown feedback mechanism contributing to polarisation. Here we show in the  zygote that the feedback relies on aPKC phosphorylation of Cdc42 at serine 71. The turnover of CDC-42 phosphorylation ensures optimal aPKC asymmetry and activity throughout polarisation by tuning Par6/aPKC association with Par3 and Cdc42. Moreover, turnover of Cdc42 phosphorylation regulates actomyosin cortex dynamics that are known to drive aPKC asymmetry. Given the widespread role of aPKC and Cdc42 in cell polarity, this form of self-regulation of aPKC may be vital for the robust control of polarisation in many cell types.

Atypical Protein Kinase C Promotes its own Asymmetric Localisation by Phosphorylating Cdc42 in the  zygote.

Reproducible tissue morphology is a fundamental feature of embryonic development. To ensure such robustness during tissue morphogenesis, inherent noise in biological processes must be buffered. While redundant genes, parallel signaling pathways and intricate network topologies are known to reduce noise, over the last few years, mechanical properties of tissues have been shown to play a vital role. Here, taking the example of somite shape changes, I will discuss how tissues are highly plastic in their ability to change shapes leading to increased precision and reproducibility.

An emerging role for tissue plasticity in developmental precision.

External bilateral symmetry is a prevalent feature in vertebrates, which emerges during early embryonic development. To begin with, vertebrate embryos are largely radially symmetric before transitioning to bilaterally symmetry, after which, morphogenesis of various bilateral tissues (e.g somites, otic vesicle, limb bud), and structures (e.g palate, jaw) ensue. While a significant amount of work has probed the mechanisms behind symmetry breaking in the left-right axis leading to asymmetric positioning of internal organs, little is known about how bilateral tissues emerge at the same time with the same shape and size and at the same position on the two sides of the embryo. By discussing emergence of symmetry in many bilateral tissues and structures across vertebrate model systems, we highlight that understanding symmetry establishment is largely an open field, which will provide deep insights into fundamental problems in developmental biology for decades to come.

ArticleTotal : 2	Year
Publication title	2024
Publication title Cited by 1	2025

Article	Year
Atypical Protein Kinase C Promotes its own Asymmetric Localisation by Phosphorylating Cdc42 in the zygote. bioRxiv : the preprint server for biology\| PubMed ID: 38009101	2024
An emerging role for tissue plasticity in developmental precision. Biochemical Society transactions\| PubMed ID: 38716859	2024
Emergence of a left-right symmetric body plan in vertebrate embryos. Current topics in developmental biology\| PubMed ID: 38729680	2024

Sundar Ram Naganathan

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