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Gou, L.

Publications and source records attributed to Gou, L..

2 recordsLinked to original sources

Extrastriate Connectivity of the Mouse Dorsal Lateral Geniculate Thalamus

The mammalian visual system is one of the most well-studied brain systems. Visual information from the retina is relayed to the dorsal lateral geniculate nucleus of the thalamus (LGd). The LGd then projects topographically to primary visual cortex (VISp) to mediate visual perception. In this view, the VISp is a critical network hub where visual information must traverse LGd-VISp circuits to reach higher-order extrastriate visual cortices. However, decades of conflicting reports in a variety of mammals support or refute the existence of extrastriate LGd connections that can bypass the VISp. Here, we provide evidence of bidirectional extrastriate connectivity with the mouse LGd. Using small, discrete coinjections of anterograde and retrograde tracers within the thalamus and cortex, our cross-validated approach identified bidirectional thalamocortical connectivity between LGd and extrastriate visual cortices. Our findings support the existence of extrastriate LGd circuits and provide novel understanding of LGd organization in rodent visual system.

neuroscience

The genetic basis of mutation rate variation in yeast

Mutations are the root source of genetic variation and underlie the process of evolution. Although the rates at which mutations occur vary considerably between species, little is known about differences within species, or the genetic and molecular basis of these differences. Here we leveraged the power of the yeast Saccharomyces cerevisiae as a model system to uncover natural genetic variants that underlie variation in mutation rate. We developed a high-throughput fluctuation assay and used it to quantify mutation rates in natural yeast isolates and in 1040 segregant progeny from a cross between BY, a lab strain, and RM, a wine strain. We observed that mutation rate varies among yeast strains and is highly heritable (H2=0.46). We performed linkage mapping in the segregants and identified four quantitative trait loci (QTLs) underlying mutation rate variation in the cross. We fine-mapped two QTLs to the underlying causal genes, RAD5 and MKT1, that contribute to mutation rate variation. These genes also underlie sensitivity to the DNA damaging agents 4NQO and MMS, suggesting a connection between spontaneous mutation rate and mutagen sensitivity.

genetics