Authors: Caldarelli, P., Chamolly, A., Villedieu, A. et al.

Publishing Date: 26 September 2024

doi: https://doi.org/10.1038/s41586-024-07934-8

Abstract: Early amniote development is highly self-organized, capable of adapting to interference through local and long-range cell–cell interactions. This process, called embryonic regulation, has been well illustrated in experiments on avian embryos, in which subdividing the epiblast disk into different parts not only redirects cell fates to eventually form a complete and well-proportioned embryo at its original location, but also leads to the self-organization of additional, fully formed embryos in the other separated parts. The cellular interactions underlying embryonic self-organization are widely believed to be mediated by molecular signals, yet the identity of such signals is unclear. Here, by analysing intact and mechanically perturbed quail embryos, we show that the mechanical forces that drive embryogenesis self-organize, with contractility locally self-activating and the ensuing tension acting as a long-range inhibitor. This mechanical feedback governs the persistent pattern of tissue flows that shape the embryo and also steers the concomitant emergence of embryonic territories by modulating gene expression, ensuring the formation of a single embryo under normal conditions, yet allowing the emergence of multiple, well-proportioned embryos after perturbations. Thus, mechanical forces act at the core of embryonic self-organization, shaping both tissues and gene expression to robustly yet plastically canalize early development.

Notes: This paper was presented by Vaishnav Manoj in BioBulletin 31 Jan '25 edition.

Authors: Shigeru Negi, Miki Imanishi, Mami Hamori, Yuka Kawahara-Nakagawa, Wataru Nomura, Kanae Kishi, Nobuhito Shibata & Yukio Sugiura

Publishing Date: 07 Feb 2023

doi: https://doi.org/10.1007/s00775-023-01991-6

Abstract: Zinc finger proteins are abundant in the human proteome and are responsible for a variety of functions. The domains that constitute zinc finger proteins are compact spherical structures, each comprising approximately 30 amino acid residues, but they also have precise molecular factor functions: zinc binding and DNA recognition. Due to the biological importance of zinc finger proteins and their unique structural and functional properties, many artificial zinc finger proteins have been created and are expected to improve their functions and biological applications. In this study, we review previous studies on the redesign and application of artificial zinc finger proteins, focusing on the experimental results obtained by our research group. In addition, we systematically review various design strategies used to construct artificial zinc finger proteins and discuss in detail their potential biological applications, including gene editing. This review will provide relevant information to researchers involved or interested in the field of artificial zinc finger proteins as a potential new treatment for various diseases.

Notes: This paper was presented by Rudra Pratap Swain in BioBulletin 18 Oct '24 edition.

Authors: Kevin J. Gaston

Publishing Date: 11 May 2000

doi: https://doi.org/10.1038/35012228

Abstract: To a first approximation, the distribution of biodiversity across the Earth can be described in terms of a relatively small number of broad-scale spatial patterns. Although these patterns are increasingly well documented, understanding why they exist constitutes one of the most significant intellectual challenges to ecologists and biogeographers. Theory is, however, developing rapidly, improving in its internal consistency, and more readily subjected to empirical challenge.

Notes: This paper was presented by Aniket VR in BioBulletin 15 Nov '24 edition.

Authors: Hiroshi HAMADA

Publishing Date: 31 July 2020

doi:  https://doi.org/10.2183/pjab.96.021

Abstract: Although the human body appears superficially symmetrical with regard to the left–right (L-R) axis, most visceral organs are asymmetric in terms of their size, shape, or position. Such morphological asymmetries of visceral organs, which are essential for their proper function, are under the control of a genetic pathway that operates in the developing embryo. In many vertebrates including mammals, the breaking of L-R symmetry occurs at a structure known as the L-R organizer (LRO) located at the midline of the developing embryo. This symmetry breaking is followed by transfer of an active form of the signaling molecule Nodal from the LRO to the lateral plate mesoderm (LPM) on the left side, which results in asymmetric expression of Nodal (a left-side determinant) in the left LPM. Finally, L-R asymmetric morphogenesis of visceral organs is induced by Nodal-Pitx2 signaling. This review will describe our current understanding of the mechanisms that underlie the generation of L-R asymmetry in vertebrates, with a focus on mice.

Notes: This paper was presented by Nimal Archish Kannan in BioBulletin 22 Oct '24 edition.

Authors: Jana Škerlová, Jiří Brynda, Jan Šobotník, Marek Zákopčaník, Petr Novák, Thomas Bourguignon, David Sillam-Dussès, Pavlína Řezáčová 

Publishing Date: 15 Aug 2024

doi: https://doi.org/10.1016/j.str.2024.07.015

Abstract: Aging workers of the termite Neocapritermes taracua can defend their colony by sacrificing themselves by body rupture, mixing the externally stored blue laccase BP76 with hydroquinones to produce a sticky liquid rich in toxic benzoquinones. Here, we describe the crystal structure of BP76 isolated from N. taracua in its native form. The structure reveals several stabilization strategies, including compact folding, glycosylation, and flexible loops with disulfide bridges and tight dimer interface. The remarkable stability of BP76 maintains its catalytic activity in solid state during the lifespan of N. taracua workers, providing old workers with an efficient defensive weapon to protect their colony.

Notes: This paper was presented by A Simanchal Dora in BioBulletin 20 Sep '24 edition.