Cytoplasmic poly(A) polymerase from sea urchin eggs, merogons, amd embryos

Journal Article · Sun Jan 01 04:00:00 EST 1978 · Dev. Biol.; (United States)

DOI:https://doi.org/10.1016/0012-1606(78)90116-1· OSTI ID:6594124

Slater, D W ^[1]; Slater, I; Bollum, F J

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1. National Inst. of Child Health and Human Development, Baltimore, MD

The presence of cytoplasmic poly(A) polymerase has been established in sea urchin eggs and four-cell embryos by subcellular fractionation and use of enucleate egg halves. ATP is the only ribonucleoside triphosphate incorporated. This incorporation is time dependent, contingent on input protein concentration, and immune to a variety of antimetabolites known to inhibit DNA-directed RNA synthesis. Both the unfertilized egg and the four-cell embryo cytoplasmic poly(A) polymerase activities display a preference for Mn/sup 2 +/. While oligo(A)/sub 4/ is inactive as a primer, addition of oligo(A)/sub 16/, poly(A)/sub 45/ and poly(A)/sub 90/ stimulates ATP incorporation. On a unit per milligram protein basis, the endogeneous activity associated with cytoplasmic fractions obtained from nucleate and enucleate egg halves is 36 and 83% that obtained with the cytoplasmic fraction prepared from the unfertilized egg. In the presence of oligo (A)/sub 16/, both the nucleate and enucleate egg halves exhibit 81% of the activity associated with the unfertilized egg cytoplasmic fraction. The level of Mn/sup 2 +/ cytoplasmic poly(A) polymerase activity from the four-cell embryo is approximately 50% that of the unfertilized egg. This decrease does not appear to be due to either a postfertilization alteration in the subcellular localization of poly(A) polymerase or an increase in RNase activity. Supplementation with oligo(A)/sub 16/ failed to restore the four-cell embryo cytoplasmic poly(A) polymerase potential to a level comparable to that of the unfertilized egg. Suppression of postfertilization protein synthesis by emetine, however, prevents this developmental decline in ATP incorporation thereby suggesting that postfertilization cytoplasmic poly(A) polymerase activity is subject to negative translational control.

• OSTI ID: 6594124
• Journal Information: Dev. Biol.; (United States), Journal Name: Dev. Biol.; (United States) Vol. 63; ISSN DEBIA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
AQUATIC ORGANISMS
ATP
BIOLOGY
BIOSYNTHESIS
CELL CONSTITUENTS
CYTOCHEMISTRY
CYTOLOGY
CYTOPLASM
DNA
ECHINODERMS
EGGS
ELEMENTS
EMBRYOS
ENZYMES
INVERTEBRATES
MANGANESE
METALS
NUCLEIC ACIDS
NUCLEOTIDES
ORGANIC COMPOUNDS
PHOSPHOTRANSFERASES
POLYMERASES
PROTEINS
RNA
RNA-ASE
SEA URCHINS
SYNTHESIS
TRANSFERASES
TRANSITION ELEMENTS