Targeted STIM deletion impairs calcium homeostasis, NFAT activation, and growth of smooth muscle.

The Ca(2+)-sensing stromal interaction molecule (STIM) proteins are crucial Ca(2+) signal coordinators. Cre-lox technology was used to generate smooth muscle (sm)-targeted STIM1-, STIM2-, and double STIM1/STIM2-knockout (KO) mouse models, which reveal the essential role of STIM proteins in Ca(2+) homeostasis and their crucial role in controlling function, growth, and development of smooth muscle cells (SMCs). Compared to Cre(+/-) littermates, sm-STIM1-KO mice showed high mortality (50% by 30 d) and reduced bodyweight.

Oocyte spindle proteomics analysis leading to rescue of chromosome congression defects in cloned embryos.

Embryos produced by somatic cell nuclear transfer (SCNT) display low term developmental potential. This is associated with deficiencies in spindle composition prior to activation and at early mitotic divisions, including failure to assemble certain proteins on the spindle. The protein-deficient spindles are accompanied by chromosome congression defects prior to activation and during the first mitotic divisions of the embryo.

Positive and negative cis-regulatory elements directing postfertilization maternal mRNA translational control in mouse embryos.

Mechanisms providing for temporally complex patterns of maternal mRNA translation after fertilization are poorly understood. We employed bioinformatics analysis to compare populations of mRNAs enriched specifically on polysomes at the metaphase II (MII) stage oocyte and late one-cell stages and a detailed deletion/truncation series to identify elements that regulate translation. We used the Bag4 3' untranslated region (UTR) as a model.

Oocyte quality and maternal control of development.

The oocyte is a unique and highly specialized cell responsible for creating, activating, and controlling the embryonic genome, as well as supporting basic processes such as cellular homeostasis, metabolism, and cell cycle progression in the early embryo. During oogenesis, the oocyte accumulates a myriad of factors to execute these processes. Oogenesis is critically dependent upon correct oocyte-follicle cell interactions.

Expression of microRNA processing machinery genes in rhesus monkey oocytes and embryos of different developmental potentials.

MicroRNAs (miRNAs) are a class of small RNAs that silence gene expression. In animal cells, miRNAs bind to the 3' untranslated regions of specific mRNAs and inhibit their translation. The correct regulation of mRNA expression by miRNAs is believed to be important for oocyte maturation, early development and implantation.

Role of glucose in cloned mouse embryo development.

Cloned mouse embryos display a marked preference for glucose-containing culture medium, with enhanced development to the blastocyst stage in glucose-containing medium attributable mainly to an early beneficial effect during the first cell cycle. This early beneficial effect of glucose is not displayed by parthenogenetic, fertilized, or tetraploid nuclear transfer control embryos, indicating that it is specific to diploid clones. Precocious localization of the glucose transporter SLC2A1 to the cell surface, as well as increased expression of glucose transporters and increased uptake of glucose at the one- and two-cell stages, is also seen in cloned embryos.

Analysis of polysomal mRNA populations of mouse oocytes and zygotes: dynamic changes in maternal mRNA utilization and function.

Transcriptional activation in mammalian embryos occurs in a stepwise manner. In mice, it begins at the late one-cell stage, followed by a minor wave of activation at the early two-cell stage, and then the major genome activation event (MGA) at the late two-cell stage. Cellular homeostasis, metabolism, cell cycle, and developmental events are orchestrated before MGA by time-dependent changes in the array of maternal transcripts being translated.