We have investigated the fate of the RNA components of small ribonucleoprotein particles in apoptotic cells. We show that the cytoplasmic Ro ribonucleoprotein-associated Y RNAs are specifically and rapidly degraded during apoptosis via a caspase-dependent mechanism. This is the first study describing the selective degradation of a specific class of small structural RNA molecules in apoptotic ce...

The basiphil cell granules of the human anterior pituitary react positively with Gram's stain, but no specific differentiation of these granules occurs when the iodine treatment is omitted. The granules of the acidophil cells are Gram-negative. Various workers have suggested a connexion between the Gram reaction of various micro-organisms and the presence of ribonucleoprotein, and the pituitary...

The Tap protein mediates the sequence nonspecific nuclear export of cellular mRNAs as well as the sequence-specific export of retroviral mRNAs bearing the constitutive transport element (CTE). Previously, the structures of individual Tap subdomains, including ribonucleoprotein and leucine-rich repeat domains, have been described. Here, we report the crystal structure of a functional CTE RNA-bin...

RNase mitochondrial RNA processing (MRP) is a site-specific endoribonuclease located in both the nucleus and mitochondria of vertebrate cells. The enzyme is a ribonucleoprotein whose RNA component has been shown to be encoded by a nuclear gene. Because RNase MRP is particular in its substrate requirement, RNA-RNA interaction has been proposed as important for the cleavage reaction. A secondary ...