Two Tetranucleotide Repeats within the Xq21.3/Yp11.2 Human Specific Region of Homology and Their Conservation in Primate Evolution

The neocortex has expanded during mammalian evolution. Overexpression studies in developing mouse and ferret neocortex have implicated the human-specific gene ARHGAP11B in neocortical expansion, but the relevance for primate evolution has been unclear. Here, we provide functional evidence that ARHGAP11B causes expansion of the primate neocortex. ARHGAP11B expressed in fetal neocortex of the common marmoset under control of the gene’s own (human) promoter increased the numbers of basal radial glia progenitors in the marmoset outer subventricular zone, increased the numbers of upper-layer neurons, enlarged the neocortex, and induced its folding. Thus, the human-specific ARHGAP11B drives changes in development in the nonhuman primate marmoset that reflect the changes in evolution that characterize human neocortical development.

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Human-Specific SNP in Obesity Genes, Adrenergic Receptor Beta2 (ADRB2), Beta3 (ADRB3), and PPAR γ2 (PPARG), during Primate Evolution

PLoS ONE ◽

10.1371/journal.pone.0043461 ◽

2012 ◽

Vol 7 (8) ◽

pp. e43461 ◽

Cited By ~ 18

Author(s):

Akiko Takenaka ◽

Shin Nakamura ◽

Fusako Mitsunaga ◽

Miho Inoue-Murayama ◽

Toshifumi Udono ◽

...

Keyword(s):

Adrenergic Receptor ◽

Primate Evolution ◽

Obesity Genes ◽

Human Specific

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Human-specific ARHGAP11B is necessary and sufficient for human-type basal progenitor levels in primate brain organoids

10.1101/2020.10.01.322792 ◽

2020 ◽

Author(s):

Jan Fischer ◽

Jula Peters ◽

Takashi Namba ◽

Wieland B. Huttner ◽

Michael Heide

Keyword(s):

Genetic Manipulation ◽

Primate Evolution ◽

Specific Gene ◽

Major Contributor ◽

Human Neocortex ◽

Primate Brain ◽

Basal Progenitor ◽

And Function ◽

Necessary And Sufficient ◽

Human Specific

AbstractBased on studies in various animal models, including developing ferret neocortex (Kalebic et al., 2018), the human-specific gene ARHGAP11B has been implicated in human neocortex expansion. However, the extent of its contribution to this expansion during primate evolution is unknown. Here we addressed this issue by genetic manipulation of ARHGAP11B levels and function in chimpanzee and human cerebral organoids. Interference with ARHGAP11B’s function in human cerebral organoids caused a massive decrease, down to a chimpanzee level, in the proliferation and abundance of basal progenitors, the progenitors thought to have a key role in neocortex expansion. Conversely, ARHGAP11B expression in chimpanzee cerebral organoids resulted in a doubling of cycling basal progenitors. Taken together, our findings demonstrate that ARHGAP11B is necessary and sufficient to maintain the elevated basal progenitor levels that characterize the fetal human neocortex, suggesting that this human-specific gene was a major contributor to neocortex expansion during human evolution.

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Review for "Modeling Human‐specific Interlaminar Astrocytes in the Mouse Cerebral Cortex"

10.1002/cne.24979/v2/review1 ◽

2020 ◽

Author(s):

Alexei Verkhratsky

Keyword(s):

Cerebral Cortex ◽

Mouse Cerebral Cortex ◽

Human Specific

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A technique to prepare cross-sectional TEM specimens of semiconducting devices

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014508x ◽

1986 ◽

Vol 44 ◽

pp. 742-743

Author(s):

A. K. Rai ◽

P. P. Pronko

Keyword(s):

Thin Films ◽

Surface Region ◽

Sample Surface ◽

Specific Region ◽

Cross Sectional ◽

Thin Sections ◽

The Past ◽

Device Structures ◽

Ion Implanted

Several techniques have been reported in the past to prepare cross(x)-sectional TEM specimen. These methods are applicable when the sample surface is uniform. Examples of samples having uniform surfaces are ion implanted samples, thin films deposited on substrates and epilayers grown on substrates. Once device structures are fabricated on the surfaces of appropriate materials these surfaces will no longer remain uniform. For samples with uniform surfaces it does not matter which part of the surface region remains in the thin sections of the x-sectional TEM specimen since it is similar everywhere. However, in order to study a specific region of a device employing x-sectional TEM, one has to make sure that the desired region is thinned. In the present work a simple way to obtain thin sections of desired device region is described.

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