Positive selection at the ASPM gene coincides with brain size enlargements in cetaceans

The enlargement of cetacean brain size represents an enigmatic event in mammalian evolution, yet its genetic basis remains poorly explored. One candidate gene associated with brain size evolution is the abnormal spindle-like microcephaly associated (ASPM), as mutations in this gene cause severe reductions in the cortical size of humans. Here, we investigated the ASPM gene in representative cetacean lineages and previously published sequences from other mammals to test whether the expansion of the cetacean brain matched adaptive ASPM evolution patterns. Our analyses yielded significant evidence of positive selection on the ASPM gene during cetacean evolution, especially for the Odontoceti and Delphinoidea lineages. These molecular patterns were associated with two major events of relative brain size enlargement in odontocetes and delphinoids. It is of particular interest to find that positive selection was restricted to cetaceans and primates, two distant lineages both characterized by a massive expansion of brain size. This result is suggestive of convergent molecular evolution, although no site-specific convergence at the amino acid level was found.

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Genetic basis of brain size evolution in cetaceans: insights from adaptive evolution of seven primary microcephaly (MCPH) genes

BMC Evolutionary Biology ◽

10.1186/s12862-017-1051-7 ◽

2017 ◽

Vol 17 (1) ◽

Cited By ~ 6

Author(s):

Shixia Xu ◽

Xiaohui Sun ◽

Xu Niu ◽

Zepeng Zhang ◽

Ran Tian ◽

...

Keyword(s):

Adaptive Evolution ◽

Genetic Basis ◽

Brain Size ◽

Primary Microcephaly ◽

Size Evolution

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Molecular evolutionary analysis of human primary microcephaly genes

BMC Ecology and Evolution ◽

10.1186/s12862-021-01801-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Nashaiman Pervaiz ◽

Hongen Kang ◽

Yiming Bao ◽

Amir Ali Abbasi

Keyword(s):

Evolutionary History ◽

Genetic Basis ◽

Brain Size ◽

Primate Species ◽

Evolutionary Analysis ◽

Australopithecus Afarensis ◽

Primary Microcephaly ◽

Modern Humans ◽

History Of ◽

The Brain

Abstract Background There has been a rapid increase in the brain size relative to body size during mammalian evolutionary history. In particular, the enlarged and globular brain is the most distinctive anatomical feature of modern humans that set us apart from other extinct and extant primate species. Genetic basis of large brain size in modern humans has largely remained enigmatic. Genes associated with the pathological reduction of brain size (primary microcephaly-MCPH) have the characteristics and functions to be considered ideal candidates to unravel the genetic basis of evolutionary enlargement of human brain size. For instance, the brain size of microcephaly patients is similar to the brain size of Pan troglodyte and the very early hominids like the Sahelanthropus tchadensis and Australopithecus afarensis. Results The present study investigates the molecular evolutionary history of subset of autosomal recessive primary microcephaly (MCPH) genes; CEP135, ZNF335, PHC1, SASS6, CDK6, MFSD2A, CIT, and KIF14 across 48 mammalian species. Codon based substitutions site analysis indicated that ZNF335, SASS6, CIT, and KIF14 have experienced positive selection in eutherian evolutionary history. Estimation of divergent selection pressure revealed that almost all of the MCPH genes analyzed in the present study have maintained their functions throughout the history of placental mammals. Contrary to our expectations, human-specific adoptive evolution was not detected for any of the MCPH genes analyzed in the present study. Conclusion Based on these data it can be inferred that protein-coding sequence of MCPH genes might not be the sole determinant of increase in relative brain size during primate evolutionary history.

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Different environmental variables predict body and brain size evolution in Homo

Nature Communications ◽

10.1038/s41467-021-24290-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Manuel Will ◽

Mario Krapp ◽

Jay T. Stock ◽

Andrea Manica

Keyword(s):

Environmental Factors ◽

Cognitive Abilities ◽

Net Primary Productivity ◽

Brain Size ◽

Environmental Influence ◽

Size Variation ◽

Evolutionary Pattern ◽

Statistical Framework ◽

Size Evolution ◽

Major Predictor

AbstractIncreasing body and brain size constitutes a key macro-evolutionary pattern in the hominin lineage, yet the mechanisms behind these changes remain debated. Hypothesized drivers include environmental, demographic, social, dietary, and technological factors. Here we test the influence of environmental factors on the evolution of body and brain size in the genus Homo over the last one million years using a large fossil dataset combined with global paleoclimatic reconstructions and formalized hypotheses tested in a quantitative statistical framework. We identify temperature as a major predictor of body size variation within Homo, in accordance with Bergmann’s rule. In contrast, net primary productivity of environments and long-term variability in precipitation correlate with brain size but explain low amounts of the observed variation. These associations are likely due to an indirect environmental influence on cognitive abilities and extinction probabilities. Most environmental factors that we test do not correspond with body and brain size evolution, pointing towards complex scenarios which underlie the evolution of key biological characteristics in later Homo.

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Involvement of Cys69 residue in the catalytic mechanism of N-hydroxyarylamine O-acetyltransferase of Salmonella typhimurium. Sequence similarity at the amino acid level suggests a common catalytic mechanism of acetyltransferase for S. typhimurium and higher organisms.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)42462-3 ◽

1992 ◽

Vol 267 (12) ◽

pp. 8429-8436 ◽

Cited By ~ 1

Author(s):

M Watanabe ◽

T Sofuni ◽

T Nohmi

Keyword(s):

Amino Acid ◽

Salmonella Typhimurium ◽

Acid Level ◽

Catalytic Mechanism ◽

Sequence Similarity ◽

Amino Acid Level

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Blood Uric Acid Level and IQ: A Study in Twin Families

Acta geneticae medicae et gemellologiae twin research ◽

10.1017/s0001566000007273 ◽

1984 ◽

Vol 33 (2) ◽

pp. 237-242 ◽

Cited By ~ 12

Author(s):

E. Inouye ◽

K.S. Park ◽

A. Asaka

Keyword(s):

Uric Acid ◽

Uric Acid Level ◽

Quantitative Traits ◽

Acid Level ◽

Genetic Basis ◽

Plasma Uric Acid ◽

Blood Uric Acid ◽

Twin Children ◽

Twin Families ◽

Familial Environment

AbstractApplying newly devised model, heritability (VA/VP) of plasma uric acid level, corrected for age and sex and standardized, was estimated at 0.8 in families consisting of twin parents, spouses and children. Correlation between spouses due to common genotype (ρ) was approximately 0.1, and variance due to common familial environment (VEC/Vp) was -0.3. Analysis of families of selected twin children and their parents resulted in two estimates of heritability: approximately 0.7 and 0.3, ρ being 0.34 and 0.04, and VEC/Vp being 0.04 and 0.34, respectively. Regression of IQ (y) on corrected and standardized plasma uric acid level (x) in the twin children was y = 5.56x + 123, correlation being 0.334 (p < 0.025). The result indicates a genetic basis of blood uric acid level, which may have resulted from polymorphisms in purine metabolism pathway, end product of which is uric acid in man. The significant correlation between plasma uric acid level and IQ suggests a contribution of partly common gene loci to the two quantitative traits.

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Brain size evolution in small mammals: test of the expensive tissue hypothesis

Mammalia ◽

10.1515/mammalia-2019-0134 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Ying Jiang ◽

Jia Yu Wang ◽

Xiao Fu Huang ◽

Chun Lan Mai ◽

Wen Bo Liao

Keyword(s):

Small Mammals ◽

Brain Size ◽

Reproductive Investment ◽

Generalized Least Squares ◽

Offspring Number ◽

Size Evolution ◽

Large Brain ◽

Species Evolution ◽

The Cost ◽

Expensive Tissue Hypothesis

Abstract Brain size exhibits significant changes within and between species. Evolution of large brains can be explained by the need to improve cognitive ability for processing more information in changing environments. However, brains are among the most energetically expensive organs. Enlarged brains can impose energetic demands that limit brain size evolution. The expensive tissue hypothesis (ETH) states that a decrease in the size of another expensive tissue, such as the gut, should compensate for the cost of a large brain. We studied the interplay between energetic limitations and brain size evolution in small mammals using phylogenetically generalized least squares (PGLS) regression analysis. Brain mass was not correlated with the length of the digestive tract in 37 species of small mammals after correcting for phylogenetic relationships and body size effects. We further found that the evolution of a large brain was not accompanied by a decrease in male reproductive investments into testes mass and in female reproductive investment into offspring number. The evolution of brain size in small mammals is inconsistent with the prediction of the ETH.

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Halogenation of glycopeptide antibiotics occurs at the amino acid level during non-ribosomal peptide synthesis

Chemical Science ◽

10.1039/c7sc00460e ◽

2017 ◽

Vol 8 (9) ◽

pp. 5992-6004 ◽

Cited By ~ 27

Author(s):

Tiia Kittilä ◽

Claudia Kittel ◽

Julien Tailhades ◽

Diane Butz ◽

Melanie Schoppet ◽

...

Keyword(s):

Amino Acid ◽

Peptide Synthesis ◽

Acid Level ◽

Amino Acid Level ◽

Antibiotic Biosynthesis ◽

Carrier Protein ◽

Glycopeptide Antibiotics ◽

Glycopeptide Antibiotic ◽

Protein Substrates

Halogenase enzymes involved in glycopeptide antibiotic biosynthesis accept aminoacyl-carrier protein substrates.

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Effect of adrenalectomy on convulsions induced by high-pressure oxygen

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y79-104 ◽

1979 ◽

Vol 57 (7) ◽

pp. 688-694 ◽

Cited By ~ 4

Author(s):

A. K. Singh ◽

E. W. Banister

Keyword(s):

High Pressure ◽

Acid Level ◽

Amino Acid Level ◽

Aminobutyric Acid ◽

Pressure Oxygen ◽

Significant Difference ◽

High Pressure Oxygen ◽

Brain Gaba ◽

The Brain ◽

Adrenalectomized Rats

Adrenalectomized rats exposed to high pressure oxygen (OHP) until convulsion convulse much later than sham-operated or normal rats. No significant changes in the concentration of noradrenaline (NA) and total catecholamines (TC) in the brain were noted in sham-operated or adrenalectomized rats resulting from sham or real surgery and no change occurred in these variables in normal sham-operated or adrenalectomized animals after OHP leading to convulsion. Brain adrenaline (A) concentration, however, decreased significantly in all three groups following OHP-induced convulsions. Activity of catecholamine O-methyltransferase (COMT) decreased significantly only in adrenalectomized rats. Brain γ-aminobutyric acid (GABA), glutamate, and other amino acid level remained unchanged after adrenalectomy whereas the concentration of ammonia decreased significantly when normal rats were adrenalectomized. After OHP-induced convulsions, the concentrations of brain GABA and glutamate decreased and ammonia and glutamine plus asparagine increased significantly in normal, sham-operated, and adrenalectomized rats. In the blood no significant difference was noted in the concentration of the catecholamines, ammonia, and amino acids either in normal or sham-operated rats. In adrenalectomized rats, the blood A and NA concentrations decreased significantly and tyrosine increased significantly. The concentration of NA, ammonia, and glutamine plus asparagine in rats from all three groups increased after OHP-induced convulsions, whereas the concentration of glutamate decreased significantly. Since the concentration of A increased significantly after convulsions in normal and sham-operated rats but did not change in adrenalectomized rats, it might be proposed that adrenalectomy protects against OHP-induced convulsions by reducing the circulating concentration of A and ammonia.However, these are not the only factors involved in the protection since the sham-operated rats also convulsed much later than normal rats but had similar ammonia and A concentrations to normal animals.

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