Decreasing glucagon action lowers the blood glucose and may be useful therapeutically for diabetes. However, interrupted glucagon signaling leads to α cell proliferation. To identify postulated hepatic-derived circulating factor(s) responsible for α cell proliferation, we used transcriptomics/proteomics/metabolomics in three models of interrupted glucagon signaling and found that proliferation of mouse, zebrafish, and human α cells was mTOR and FoxP transcription factor dependent. Changes in hepatic amino acid (AA) catabolism gene expression predicted the observed increase in circulating AAs. Mimicking these AA levels stimulated α cell proliferation in a newly developed in vitro assay with L-glutamine being a critical AA. α cell expression of the AA transporter Slc38a5 was markedly increased in mice with interrupted glucagon signaling and played a role in α cell proliferation. These results indicate a hepatic α islet cell axis where glucagon regulates serum AA availability and AAs, especially L-glutamine, regulate α cell proliferation and mass via mTOR-dependent nutrient sensing.
Interactive Vision In The Life SciencesCombining speed, precision and ease-of-use, Imaris provides an impressive range of capabilities for working with three-dimensional images. Move easily between simple and advanced 3D views. Use flexible editing and processing functions, such as interactive surface rendering and object slicing capabilities. And output to standard TIFF, Quicktime and AVI formats. Imaris accepts virtually all image formats that are used in confocal microscopy and many of those used in wide-field image acquisition.BitPlane, Inc. also releases the following companion products:- ImarisXT is a multi-functional two-way interface from Imaris to both classic programming languages and to Matlab.- Imaris MeasurementPro and Imaris Track provide the ability to segment and follow the movement of independent objects in a 3D image over time. Objects can either be Surface Objects or Spots, created automatically or manually.- ImarisColoc enables users to easily isolate, visualize, and quantify regional overlap in 3D and 4D images and automates the process of selecting colocalized image areas.
Statistical software package for data analysis, hypothesis testing, and modeling. The software can capable perform mathematical calculations (including biostatistics) and graphical plotting such as curve fitting (nonlinear regression) and scientific graphing.
SciCrunch is a data sharing and display platform. Anyone can create a custom portal where they can select searchable subsets of hundreds of data sources, brand their web pages and create their community. SciCrunch will push data updates automatically to all portals on a weekly basis. User communities can also add their own data to SciCrunch, however this is not currently a free service.