CBM Archives | Page 13 of 22 | Centre de Biophysique Moléculaire, CNRS

How the hydrothermal environment of Primeval Earth may have influenced the choice of sugar in DNA and RNA

CBM scientists give answers in a publication published in the Journal Nature Communications. Why is Furanose the only sugar found in the composition of DNA and RNA while this form of sugar is not the most stable, so not the most abundant, in temperature conditions and pressure we are currently experiencing? These are the hydrothermal sources, omnipresent on the surface of the primitive land, and their complex thermal influence, which could be at the origin of this selectivity. This study conducted by scientists from the Molecular Biophysics Center, which is the subject of an article in the Nature Communications journal, should make it possible to better understand why and how molecules come together to give life in a primitive geological context.

Reference

Avinash Vicholous Dass, Thomas Georgelin, Frances Westall, Frédéric Foucher, Paolo De Los Rios, Daniel Maria Busiello, Shiling Liand & Francesco Piazza
Equilibrium and non-equilibrium furanose selection in the ribose isomerisation network
Nature Communications, 12 2749 (2021) https://www.nature.com/articles/s41467-021-22818-5

See the news on the site of the Institute of Chemistry

Biotechnocentre 33rd conference

The 33rd Biotechnocentre conference will be held on October 7 and 8, 2021 at Center Parcs Domaine Les Hauts de Bruyères - Rue Lamotte - 41 600 Chaumont-sur-Tharonne.

With the participation of Doctoral School 549 "Santé, Sciences Biologiques et Chimie du Vivant" (SSBCV).

Among the speakers announced, Vincent Aucagne, head of the thematic group "Synthetic proteins and bioorthogonal chemistry" " will give a conference entitled "Methodological developments for the chemical synthesis of proteins"

Registration before September 3, 2021 at biotechnocentre@sfr.fr

See the poster

Conferences program

When a non-conserved protein domain becomes essential

Rho-dependent termination of transcription is a critical regulatory mechanism specific to bacteria. In a subset of species including most Actinobacteria and Bacteroidetes, the Rho factor contains a large, poorly conserved N-terminal insertion domain (NID) of cryptic function. Through the first characterization of an actinobacterial Rho factor containing a very large NID (~40% of total mass), we show that such a non-conserved protein domain can be essential for activity. Without NID, the Rho factor of Bacteroides fragilis (_BfRho) indeed cannot induce transcription termination and displays a reduced affinity for RNA. Intriguingly, the presence of a NID in _BfRho is not correlated to the lack of residues or motifs deemed essential in NID-less Rho factors from evolutionary distinct species. The NID requirement is probably linked to the coevolution of partner feature(s) such as lineage-specific RNA polymerase domains and/or low G+C content of the B. fragilis transcriptome. Our data thus highlight that ‘essential function’ does not always rhyme with ‘structural conservation’.

Simon I., Delaleau M., Schwartz A., Boudvillain M.
A Large Insertion Domain in the Rho Factor From a Low G + C, Gram-negative Bacterium is Critical for RNA Binding and Transcription Termination Activity
Journal of Molecular Biology (2021) 433 (15) 167060 - Doi : 10.1016/j.jmb.2021.167060

Biodiversity skepticism?

Based on analysis of time series of abundances of insect species in the United States, Crossley et al. reported in Nature Ecology & Evolution (August 2020) that there is no evidence of a global decline in insect abundance or diversity in the United States, this for both natural and anthropogenic sites. Their study described the apparent robustness of insect populations in the U.S. as reassuring, in contrast to recent studies reporting dramatic declines in their abundance around the world.

However, a multidisciplinary consortium including researchers from INRAE, the University of Rennes and CNRS identified major problems in the Crossley et al. paper concerning: 1) statistical analysis and 2) inconsistencies in data selection. The consortium demonstrates, in a commentary published in Nature Ecology & Evolution Desquilbet et al. , that these biases call into question the conclusions of Crossley et al.

This is the second time (see here) that a high-ranking publication downplaying insect declines has been subject to methodological criticisms. These studies raise the question of a "biodiversity-skepticism" within the scientific community. In order to implement an appropriate protection of biodiversity, public decision-makers need an informed diagnosis that is not clouded by biased studies which slow down decision-making.

Reference :
Desquilbet M, Cornillon PA, Gaume L & Bonmatin JM (2021)
Matters arising: Adequate statistical modelling and data selection are essential when analysing abundance and diversity trends
Nature Ecology & Evolution doi : https://www.nature.com/articles/s41559-021-01427-x

J.-M. Bonmatin co-author of an article in One Health (18 March 2021)

The “One Health” concept links environmental, animal (wild & livestock) and human health. It is increasingly being argued (e.g. Covid-19) and is now essential for the preservation of ecosystems and public health. Researchers from the universities of Leuven (BE), Sorbonne-CNRS-IRD-INRAE-UPEC (FR), CARI (BE), FNOSAD (FR) and the Centre for Molecular Biophysics (CNRS), have applied this concept to the case of biocides and veterinary products (including pesticides) that are used to treat livestock and that impact pollinators. These researchers have shown that these "multi-use substances" present (among other things) proven risks for bees and consequently need to be better assessed before being placed on the market. This work was initiated at the CBM in 2019: see here & here (Italian).

Reference : Mahefarisoa KL, Simon Delso N, Zaninotto V, Colin ME & Bonmatin JM (2021) The Threat of Veterinary Medicinal Products and Biocides on Pollinators: A One Health Perspective, One Health, https://doi.org/10.1016/j.onehlt.2021.100237

SFNano Webinar – March 31st, 2021

March 31st, 2021 3:30 – 6:00 pm (Paris Time Zone / CET)

MRNA vaccines have experienced an unprecedented burst in basic and clinical research. These vaccines were among the first available vaccines to fight the Covid-19 pandemic and they demonstrated the potency and versatility of mRNA technology to protect against infectious disease. As this new delivery technology is going to be applied to hundreds of millions of people in the European Community and around the world, this webinar will present the key features of lipid nanoparticles (LNPs) used for the COVID-19 mRNA vaccine and will draw first lessons learned for further vaccine development and beyond for new mRNA therapies. Find out more.

Online registration