MicroRNA Regulation of Cell Lineages in Mouse and Human Embryonic Stem Cells

SummaryCell fate decisions of pluripotent embryonic stem (ES) cells are dictated by activation and repression of lineage-specific genes. Numerous signaling and transcriptional networks progressively narrow and specify the potential of ES cells. Whether specific microRNAs help refine and limit gene expression and, thereby, could be used to manipulate ES cell differentiation has largely been unexplored. Here, we show that two serum response factor (SRF)-dependent muscle-specific microRNAs, miR-1 and miR-133, promote mesoderm formation from ES cells but have opposing functions during further differentiation into cardiac muscle progenitors. Furthermore, miR-1 and miR-133 were potent repressors of nonmuscle gene expression and cell fate during mouse and human ES cell differentiation. miR-1's effects were in part mediated by translational repression of the Notch ligand Delta-like 1 (Dll-1). Our findings indicate that muscle-specific miRNAs reinforce the silencing of nonmuscle genes during cell lineage commitment and suggest that miRNAs may have general utility in regulating cell-fate decisions from pluripotent ES cells

El estudio del cultivo de roza = The study of shifting cultivation /

Includes indexes.Opposite pages numbered in duplicate (30 p. of 2d group and p. 1-30 of 3d group)Bibliography: p. 30-172.Mode of access: Internet

Land use in north central Ifugao [cartographic material] /

Relief shown by contours and spot heights.; Map series of land use on the Banaue rice terraces in Ifugao province, the Philippines, showing channels, drainage courses, spring waters, field terraces, ritual parcels, slopefield areas, canelands, woodlands, exposed slopes, boundaries, roads, trails, bridges, photo centre points, ground and minor control points.; Includes text, sheet index, location map, and "Index to provincial subdivisions."; "Zone 51, Clarke 1866 spheroid"; Each sheet is named and numbered individually.Philippines, north central Ifuga

Group Counselling of Underachievers

Grade 9 underachieving volunteers and non-volunteers were taught effective study skills through group reinforcement counselling. Direct and statistical controls were emphasized in the analysis. Results supported reinforcement counselling with volunteering clients. There was improved achievement of non-counselled non-volunteers who received a "study guide.