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Porcine cumulus cells are localized around oocytes and act as a specific type of granulosa that plays essential roles in the development and maturation of oocytes, the development and atresia of follicles, and the development of embryos. Studies of FAT1 have demonstrated its functions in cell-cell contact, actin dynamics, and cell growth suppression. To understand whether the FAT1 gene affects the apoptosis of porcine cumulus cells and to elucidate the mechanism of this potential action, FAT1 was knocked down using RNA interference. The lack of FAT1 resulted in stable expression of CTNNB, enhanced expression of cleaved CASP3, but decreased the BCL2/BAX ratios at both the mRNA and protein levels. These results indicated that FAT1 inhibited porcine cumulus cell apoptosis via different pathways. Taken together, these data provide new insights into the mechanisms of the association between FAT1 and porcine cumulus cell apoptosis.

We utilize the angle and momentum resolution of our apparatus to study the polarization of 375 GeV/c Sigma(+) hyperons produced by 800 GeV/c protons incident on a Cu target. By examining in detail two of our high statistics data samples, we find evidence for structure in the p(t) dependence of Sigma(+) polarization and are able to extract the x(F) dependence of the Sigma(+) polarization and compare it with x(F) behavior in the Lambda(0) and Xi(-) systems.

We have measured the branching ratio for the hyperon radiative decay ${\mathrm{\ensuremath{\Sigma}}}^{+}$\ensuremath{\rightarrow}p\ensuremath{\gamma} using the Fermilab polarized charged hyperon beam. This measurement and our previously published result on the asymmetry parameter in the same decay are part of Fermilab experiment E761. We find B(${\mathrm{\ensuremath{\Sigma}}}^{+}$\ensuremath{\rightarrow}p\ensuremath{\gamma})/B(${\mathrm{\ensuremath{\Sigma}}}^{+}$\ensuremath{\rightarrow}p${\mathrm{\ensuremath{\pi}}}^{0}$) to be [2.32\ifmmode\pm\else\textpm\fi{}0.11(stat)\ifmmode\pm\else\textpm\fi{}0.10(syst)]\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}3}$ with a sample of 31 901 events. The higher statistics and careful attention to systematic uncertainties make these significant improvements over previous measurements. We describe how our measurements were performed and briefly review the theoretical implications of these results.

We have measured the branching ratio for the hyperon radiative decay [Xi][sup [minus]][r arrow][Sigma][sup [minus]][gamma] from a sample of 211[plus minus]33 events obtained in the polarized 375 GeV/[ital c] charged hyperon beam at Fermilab. We find [ital B]([Xi][sup [minus]][r arrow][Sigma][sup [minus]][gamma]/[Xi][sup [minus]][r arrow][Lambda][sup 0][pi][sup [minus]])=(1.22[plus minus]0.23[plus minus]0.06)[times]10[sup [minus]4] where the quoted errors are statistical and systematic, respectively. We have also obtained an indication that the sign of the asymmetry parameter of this decay is positive.

Gonadotropin-regulated testicular RNA helicase (GRTH/DDX25), a testis-specific member of the DEAD-box family, is an essential post-transcriptional regulator of spermatogenesis. Failure of expression of Transition protein 2 (TP2) and Protamine 2 (Prm2) proteins (chromatin remodelers, essential for spermatid elongation and completion of spermatogenesis) with preservation of their mRNA expression was observed in GRTH-null mice (azoospermic due to failure of spermatids to elongate). These were identified as target genes for the testis-specific miR-469, which is increased in the GRTH-null mice. Further analysis demonstrated that miR-469 repressed TP2 and Prm2 protein expression at the translation level with minor effect on mRNA degradation, through binding to the coding regions of TP2 and Prm2 mRNAs. The corresponding primary-microRNAs and the expression levels of Drosha and DGCR8 (both mRNA and protein) were increased significantly in the GRTH-null mice. miR-469 silencing of TP2 and Prm2 mRNA in pachytene spermatocytes and round spermatids is essential for their timely translation at later times of spermiogenesis, which is critical to attain mature sperm. Collectively, these studies indicate that GRTH, a multifunctional RNA helicase, acts as a negative regulator of miRNA-469 biogenesis and consequently their function during spermatogenesis.

We have measured the magnetic moments of the SIGMA+ and SIGMABAR- hyperons produced by 800-GeV protons incident on a Cu target. We determine the SIGMA+ magnetic moment to be (2.4613 +/- 0.0034 +/- 0.0040)mu(N) where the uncertainties are statistical and systematic, respectively. In this first measurement we determine the magnetic moment of the SIGMABAR- to be -(2.428 +/- 0.036 +/- 0.007)mu(N). The magnetic moments of the SIGMA+ and SIGMABAR- are consistent with each other in magnitude but opposite in sign as required by CPT invariance.

We have measured the polarization of 375-GeV/c SIGMA+ and SIGMABAR- hyperons produced by 800-GeV/c protons incident on a Cu target. We find that the SIGMA+ polarization rises with increasing p(t) to a maximum of 16% at p(t) = 1.0 GeV/c and then decreases to 10% at p(t) = 1.8 GeV/c. We compare this SIGMA+ polarization with data at lower energies. The SIGMABAR- polarization has been measured for the first time. It has the same sign as the SIGMA+ but smaller magnitude in a similar kinematical region.

We have measured the asymmetry parameter (${\mathrm{\ensuremath{\alpha}}}_{\ensuremath{\gamma}}$) in the hyperon radiative decay ${\mathrm{\ensuremath{\Sigma}}}^{+}$\ensuremath{\rightarrow}p\ensuremath{\gamma} with a sample of 34 754\ifmmode\pm\else\textpm\fi{}212 events obtained in a polarized charged hyperon beam experiment at Fermilab. We find ${\mathrm{\ensuremath{\alpha}}}_{\ensuremath{\gamma}}$=-0.720\ifmmode\pm\else\textpm\fi{}0.086\ifmmode\pm\else\textpm\fi{}0.045, where the quoted errors are statistical and systematic, respectively.

We have searched for the rare hyperon radiative decay Omega- to Xi- gamma, using the Fermilab Proton Center 375 GeV/c charged hyperon beam. Our measurement of the Omega- beam fraction at 13.6 m from production is (4.8 +_ 0.4)10**(-5). No signal was found and we determine a new upper limit of (4.6 x 10**-4) at 90% CL for the Omega- to Xi- gamma branching ratio.

We have searched for the production and decay of light super-symmetric baryons produced in 800 GeV/c proton copper interactions in a charged hyperon beam experiment. We observe no evidence for the decays R+(uud \g^~) -> S(uds \g^~) pi+ and X-(ssd \g^~) -> S(uds \g^~) pi- in the predicted parent mass and lifetime ranges of 1700-2500 Mev/c2 and 50-500 ps. Production upper limits for R+ at xF=0.47, Pt=1.4 GeV/c2 and X- at xF=0.48, Pt=0.65 GeV/c2 of less than 10^-3 of all charged secondary particles produced are obtained for all but the highest masses and shortest lifetimes predicted., 9 pages, uuencoded postscript 4 figures uuencoded, tar-compressed file (submitted to PRL)