scholarly journals Evidence for reduced immune gene diversity and activity during the evolution of termites

2020 ◽  
Author(s):  
Shulin He ◽  
Thorben Sieksmeyer ◽  
Yanli Che ◽  
M. Alejandra Esparza Mora ◽  
Petr Stiblik ◽  
...  

AbstractThe evolution of biological complexity is associated with the emergence of bespoke immune systems that maintain and protect organism integrity. Unlike the well studied immunity at the cell and individual level, little is known about the origins of immunity during the transition to eusociality, a major evolutionary transition comparable to the evolution of multicellular organisms from single-celled ancestors. We tackle this by characterizing the immune gene repertoire of 18 cockroach and termite species, spanning the spectrum of solitary, subsocial and eusocial lifestyles. We identified five significant immune gene family contractions and one immune gene family expansion along the spine of a time-calibrated phylogeny, correlating with key transitions in termite sociality. In cross-species comparisons of immune gene expression, we find that termites appear to have evolved a caste-specific social defense system at the expense of individual immune protection. Our study indicates that a major transition in organismal complexity entailed a fundamental reshaping of the immune system optimized for group over individual defense.

2021 ◽  
Vol 288 (1945) ◽  
pp. 20203168
Author(s):  
Shulin He ◽  
Thorben Sieksmeyer ◽  
Yanli Che ◽  
M. Alejandra Esparza Mora ◽  
Petr Stiblik ◽  
...  

The evolution of biological complexity is associated with the emergence of bespoke immune systems that maintain and protect organism integrity. Unlike the well-studied immune systems of cells and individuals, little is known about the origins of immunity during the transition to eusociality, a major evolutionary transition comparable to the evolution of multicellular organisms from single-celled ancestors. We aimed to tackle this by characterizing the immune gene repertoire of 18 cockroach and termite species, spanning the spectrum of solitary, subsocial and eusocial lifestyles. We find that key transitions in termite sociality are correlated with immune gene family contractions. In cross-species comparisons of immune gene expression, we find evidence for a caste-specific social defence system in termites, which appears to operate at the expense of individual immune protection. Our study indicates that a major transition in organismal complexity may have entailed a fundamental reshaping of the immune system optimized for group over individual defence.


Author(s):  
John Maynard Smith ◽  
Eors Szathmary

Over the history of life there have been several major changes in the way genetic information is organized and transmitted from one generation to the next. These transitions include the origin of life itself, the first eukaryotic cells, reproduction by sexual means, the appearance of multicellular plants and animals, the emergence of cooperation and of animal societies, and the unique language ability of humans. This ambitious book provides the first unified discussion of the full range of these transitions. The authors highlight the similarities between different transitions--between the union of replicating molecules to form chromosomes and of cells to form multicellular organisms, for example--and show how understanding one transition sheds light on others. They trace a common theme throughout the history of evolution: after a major transition some entities lose the ability to replicate independently, becoming able to reproduce only as part of a larger whole. The authors investigate this pattern and why selection between entities at a lower level does not disrupt selection at more complex levels. Their explanation encompasses a compelling theory of the evolution of cooperation at all levels of complexity. Engagingly written and filled with numerous illustrations, this book can be read with enjoyment by anyone with an undergraduate training in biology. It is ideal for advanced discussion groups on evolution and includes accessible discussions of a wide range of topics, from molecular biology and linguistics to insect societies.


2021 ◽  
Vol 35 (2) ◽  
pp. 365-366
Author(s):  
Carlos E. Lara ◽  
Catherine E. Grueber ◽  
Benedikt Holtmann ◽  
Eduardo S. A. Santos ◽  
Sheri L. Johnson ◽  
...  

BMC Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Hao Song ◽  
Ximing Guo ◽  
Lina Sun ◽  
Qianghui Wang ◽  
Fengming Han ◽  
...  

Abstract Background Inhibitors of apoptosis (IAPs) are critical regulators of programmed cell death that are essential for development, oncogenesis, and immune and stress responses. However, available knowledge regarding IAP is largely biased toward humans and model species, while the distribution, function, and evolutionary novelties of this gene family remain poorly understood in many taxa, including Mollusca, the second most speciose phylum of Metazoa. Results Here, we present a chromosome-level genome assembly of an economically significant bivalve, the hard clam Mercenaria mercenaria, which reveals an unexpected and dramatic expansion of the IAP gene family to 159 members, the largest IAP gene repertoire observed in any metazoan. Comparative genome analysis reveals that this massive expansion is characteristic of bivalves more generally. Reconstruction of the evolutionary history of molluscan IAP genes indicates that most originated in early metazoans and greatly expanded in Bivalvia through both lineage-specific tandem duplication and retroposition, with 37.1% of hard clam IAPs located on a single chromosome. The expanded IAPs have been subjected to frequent domain shuffling, which has in turn shaped their architectural diversity. Further, we observed that extant IAPs exhibit dynamic and orchestrated expression patterns among tissues and in response to different environmental stressors. Conclusions Our results suggest that sophisticated regulation of apoptosis enabled by the massive expansion and diversification of IAPs has been crucial for the evolutionary success of hard clam and other molluscan lineages, allowing them to cope with local environmental stresses. This study broadens our understanding of IAP proteins and expression diversity and provides novel resources for studying molluscan biology and IAP function and evolution.


eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Daniel J Richter ◽  
Parinaz Fozouni ◽  
Michael B Eisen ◽  
Nicole King

Choanoflagellates, the closest living relatives of animals, can provide unique insights into the changes in gene content that preceded the origin of animals. However, only two choanoflagellate genomes are currently available, providing poor coverage of their diversity. We sequenced transcriptomes of 19 additional choanoflagellate species to produce a comprehensive reconstruction of the gains and losses that shaped the ancestral animal gene repertoire. We identified ~1944 gene families that originated on the animal stem lineage, of which only 39 are conserved across all animals in our study. In addition, ~372 gene families previously thought to be animal-specific, including Notch, Delta, and homologs of the animal Toll-like receptor genes, instead evolved prior to the animal-choanoflagellate divergence. Our findings contribute to an increasingly detailed portrait of the gene families that defined the biology of the Urmetazoan and that may underpin core features of extant animals.


2018 ◽  
Vol 11 (1) ◽  
pp. 232-241 ◽  
Author(s):  
David Reher ◽  
Felix M Key ◽  
Aida M Andrés ◽  
Janet Kelso
Keyword(s):  

2018 ◽  
Author(s):  
Mónica Lopes-Marques ◽  
André M. Machado ◽  
Raquel Ruivo ◽  
Elza Fonseca ◽  
Estela Carvalho ◽  
...  

AbstractFatty acids (FAs) constitute a considerable fraction of all lipid molecules with a fundamental role in numerous physiological processes. In animals, the majority of complex lipid molecules are derived from the transformation of FAs through several biochemical pathways. Yet, for FAs to enroll in these pathways they require an activation step. FA activation is catalyzed by the rate limiting action of Acyl-CoA synthases. Several Acyl-CoA enzyme families have been previously described and classified according to the chain length of FA they process. Here, we address the evolutionary history of the ACSBG gene family which activates, FA with more than 16 carbons. Currently, two different ACSBG gene families, ACSBG1 and ACSBG2, are recognized in vertebrates. We provide evidence that a wider and unequal ACSBG gene repertoire is present in vertebrate lineages. We identify a novel ACSBG-like gene lineage which occurs specifically in amphibians, ray finned fish, coelacanths and chondrichthyes named ACSBG3. Also, we show that the ACSBG2 gene lineage duplicated in the Theria ancestor. Our findings, thus offer a far richer understanding on FA activation in vertebrates and provide key insights into the relevance of comparative and functional analysis to perceive physiological differences, namely those related with lipid metabolic pathways.


BMC Genomics ◽  
2016 ◽  
Vol 17 (1) ◽  
Author(s):  
Matan Oren ◽  
Megan A. Barela Hudgell ◽  
Brian D’Allura ◽  
Jacob Agronin ◽  
Alexandra Gross ◽  
...  

2020 ◽  
Vol 287 (1919) ◽  
pp. 20192675 ◽  
Author(s):  
Emily A. O'Connor ◽  
Dennis Hasselquist ◽  
Jan-Åke Nilsson ◽  
Helena Westerdahl ◽  
Charlie K. Cornwallis

Pathogen communities can vary substantially between geographical regions due to different environmental conditions. However, little is known about how host immune systems respond to environmental variation across macro-ecological and evolutionary scales. Here, we select 37 species of songbird that inhabit diverse environments, including African and Palaearctic residents and Afro-Palaearctic migrants, to address how climate and habitat have influenced the evolution of key immune genes, the major histocompatibility complex class I (MHC-I). Resident species living in wetter regions, especially in Africa, had higher MHC-I diversity than species living in drier regions, irrespective of the habitats they occupy. By contrast, no relationship was found between MHC-I diversity and precipitation in migrants. Our results suggest that the immune system of birds has evolved greater pathogen recognition in wetter tropical regions. Furthermore, evolving transcontinental migration appears to have enabled species to escape wet, pathogen-rich areas at key periods of the year, relaxing selection for diversity in immune genes and potentially reducing immune system costs.


Sign in / Sign up

Export Citation Format

Share Document