Skip to main content
Premium Trial:

Request an Annual Quote

This Week in PNAS: Jul 24, 2018

In the early, online edition of the Proceedings of the National Academy of Sciences, researchers from Germany and the UK present findings from a single-cell analysis of blood cells in the malaria mosquito vector Anopheles gambiae. Using fluorescence activated cell sorting, single-cell RNA sequencing, imaging flow cytometry, and other approaches, the team profiled blood cell populations in a transgenic mosquito strain containing a fluorescent reporter linked to an immune response-related gene. With transcriptome sequence data for dozens of individual blood cells and two pooled blood cell samples, for example, the authors defined distinct transcriptional patterns within two blood cell populations that appear to swap some cellular markers. They note that this molecular transfer "may contribute to cellular diversity and plasticity seen across biological systems."

A team from Regeneron Pharmaceuticals and Imperial College London describe enhanced insulin secretion in mice carrying a human zinc transporter gene SLC30A8 with a known loss-of-function mutation. This mutation, known as R138X, was previously shown to protect against type 2 diabetes development in humans, the researchers say. For their new study, they inserted R138X into mice, demonstrating that the mutation could boost insulin secretion by islet cells in mice with induced hyperglycemia. "Our data suggest that the SLC30A8 R138X [loss-of-function] mutation may exert beneficial effects on glucose metabolism by increasing the capacity of [beta-cells] to secrete insulin under hyperglycemic conditions," the authors say.

Researchers from Nanjing University and elsewhere search for genes contributing to high yield in rice using a strategy that brings together pedigree analysis, whole-genome sequencing, and gene knockouts done with CRISPR-Cas9-based editing. Starting with a rice pedigree analysis that included high-yield cultivars related to the "Green Revolution" line IR8, the team used sequencing to narrow in on chromosomal blocks shared in cultivars with particularly pronounced yields, followed by gene knockout analyses to track the effects of specific genes. In addition to highlighting genes with apparent ties to yield, the authors describe clustering of rice genes with related functions. More generally, they say, the strategy used "provides a simple, robust, and fast means to identify candidate genes under directional selection."