Article Abstract:
The oocyte-type and somatic-type 5S ribosomal RNA (rRNA) in the Xenopus oocyte are processed differently. The oocyte-type 5S rRNA interacts with the 5S rRNA gene-specific transcription factor IIIA to form 7S ribonucleoprotein particles, which are stored in the cytoplasm. The somatic-type 5S rRNA interacts with ribosomal protein L5 to form 5S nucleoprotein particles that enter the nucleus and become part of the 60S ribosomal subunit. The nucleotide structure of the two types of 5S rRNA differs at six positions, which could account for their differential processing.
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Article Abstract:
Polarization of oocyte gap junction proteins is described by several studies using an exogenous protein. Results indicate that oocytes achieve higher conductances when paired at their vegetal poles than when paired at their animal poles. This asymmetry involves the action of the ooyctes's connexin protein, which can cause changes in the membrane potential. It has not been tested whether connexin molecules are inserted randomly or preferentially into the plasma membrane.
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Article Abstract:
Presence of FSH or dbc AMP enhances the production of plasminogen activator (PA) by mouse cumulus and mural granulosa cells. This FSH- and dbc AMP-induced PA synthesis is inhibited by a medium of oocyte. Oocytes modulate the abundance of its RNA to induce the inhibition. Analysis of a oocyte-secreted factor, which is responsible for the inhibition, reveals it as a heat-unstable protein and it has a molecular weight above 100 kDa.
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