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Duong, T.

Publications and source records attributed to Duong, T..

2 recordsLinked to original sources

Ral signals through a MAP4 Kinase-p38 MAP kinase cascade in C. elegans cell fate patterning.

C. elegans vulval precursor cell (VPC) fates are patterned by an EGF gradient. High dose EGF induces 1{degrees} VPC fate, while lower dose EGF contributes to 2{degrees} fate in support of LIN-12/Notch. We previously showed that the EGF 2{degrees}-promoting signal is mediated by LET-60/Ras switching effectors, from the canonical Raf-MEK-ERK MAP kinase cascade that promotes 1{degrees} fate to the non-canonical RalGEF-Ral that promotes 2{degrees} fate. Of oncogenic Ras effectors, RalGEF-Ral is by far the least well-understood. We use genetic analysis to identify an effector cascade downstream of C. elegans RAL-1/Ral, starting with an established Ral binding partner, Exo84 of the exocyst complex. Additionally, RAL-1 signals through GCK-2, a CNH domain-containing MAP4 kinase, and PMK-1/p38 MAP kinase cascade to promote 2{degrees} fate. Our study delineates a Ral-dependent developmental signaling cascade in vivo, thus providing the mechanism by which lower EGF dose is transduced.

developmental biology

Integrative Single-Cell Analysis By Transcriptional And Epigenetic States In Human Adult Brain

Detailed characterization of the cell types comprising the highly complex human brain is essential to understanding its function. Such tasks require highly scalable experimental approaches to examine different aspects of the molecular state of individual cells, as well as the computational integration to produce unified cell state annotations. Here we report the development of two highly scalable methods (snDrop-Seq and scTHS-Seq), that we have used to acquire nuclear transcriptome and DNA accessibility maps for thousands of single cells from the human adult visual and frontal cortex. This has led to the best-resolved human neuronal subtypes to date, identification of a majority of the non-neuronal cell types, as well as the cell-type specific nuclear transcriptome and DNA accessibility maps. Integrative analysis allowed us to identify transcription factors and regulatory elements shaping the state of different brain cell types, and to map genetic risk factors of human brain common diseases to specific pathogenic cell types and subtypes.

genomics