Browsing by Author "Roulhac, Petra L"

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    Convergent differential regulation of SLIT-ROBO axon guidance genes in the brains of vocal learners.
    (J Comp Neurol, 2015-04-15) Wang, Rui; Chen, Chun-Chun; Hara, Erina; Rivas, Miriam V; Roulhac, Petra L; Howard, Jason T; Chakraborty, Mukta; Audet, Jean-Nicolas; Jarvis, Erich D
    Only a few distantly related mammals and birds have the trait of complex vocal learning, which is the ability to imitate novel sounds. This ability is critical for speech acquisition and production in humans, and is attributed to specialized forebrain vocal control circuits that have several unique connections relative to adjacent brain circuits. As a result, it has been hypothesized that there could exist convergent changes in genes involved in neural connectivity of vocal learning circuits. In support of this hypothesis, expanding on our related study (Pfenning et al. [2014] Science 346: 1256846), here we show that the forebrain part of this circuit that makes a relatively rare direct connection to brainstem vocal motor neurons in independent lineages of vocal learning birds (songbird, parrot, and hummingbird) has specialized regulation of axon guidance genes from the SLIT-ROBO molecular pathway. The SLIT1 ligand was differentially downregulated in the motor song output nucleus that makes the direct projection, whereas its receptor ROBO1 was developmentally upregulated during critical periods for vocal learning. Vocal nonlearning bird species and male mice, which have much more limited vocal plasticity and associated circuits, did not show comparable specialized regulation of SLIT-ROBO genes in their nonvocal motor cortical regions. These findings are consistent with SLIT and ROBO gene dysfunctions associated with autism, dyslexia, and speech sound language disorders and suggest that convergent evolution of vocal learning was associated with convergent changes in the SLIT-ROBO axon guidance pathway.
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    Convergent transcriptional specializations in the brains of humans and song-learning birds.
    (Science, 2014-12-12) Pfenning, Andreas R; Hara, Erina; Whitney, Osceola; Rivas, Miriam V; Wang, Rui; Roulhac, Petra L; Howard, Jason T; Wirthlin, Morgan; Lovell, Peter V; Ganapathy, Ganeshkumar; Mouncastle, Jacquelyn; Moseley, M Arthur; Thompson, J Will; Soderblom, Erik J; Iriki, Atsushi; Kato, Masaki; Gilbert, M Thomas P; Zhang, Guojie; Bakken, Trygve; Bongaarts, Angie; Bernard, Amy; Lein, Ed; Mello, Claudio V; Hartemink, Alexander J; Jarvis, Erich D
    Song-learning birds and humans share independently evolved similarities in brain pathways for vocal learning that are essential for song and speech and are not found in most other species. Comparisons of brain transcriptomes of song-learning birds and humans relative to vocal nonlearners identified convergent gene expression specializations in specific song and speech brain regions of avian vocal learners and humans. The strongest shared profiles relate bird motor and striatal song-learning nuclei, respectively, with human laryngeal motor cortex and parts of the striatum that control speech production and learning. Most of the associated genes function in motor control and brain connectivity. Thus, convergent behavior and neural connectivity for a complex trait are associated with convergent specialized expression of multiple genes.
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    Microproteomics: quantitative proteomic profiling of small numbers of laser-captured cells.
    (Cold Spring Harb Protoc, 2011-02-01) Roulhac, Petra L; Ward, James M; Thompson, J Will; Soderblom, Erik J; Silva, Michael; Moseley, M Arthur; Jarvis, Erich D