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Cytoplasmic retention of Xenopus nuclear factor 7 before the mid blastula transition uses a unique anchoring mechanism involving a retention domain and several phosphorylation sites.
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Xenopus nuclear factor 7 (xnf7) is a maternally expressed protein that belongs to the B-box zinc finger gene family consisting of transcription factors, protooncogenes, and ribonucleoproteins. Its function is regulated by retention in the cytoplasm from oocyte maturation until the mid blastula transition (MBT) when it reenters the nucleus. We defined a 22-amino acid cytoplasmic retention domain (CRD) in xnf7 that functioned cooperatively with two phosphorylation sites within the xnf7 molecule to retain the protein in the cytoplasm until the MBT. Deletion of this region or mutations in the phosphorylation sites resulted in the early entry of xnf7 into the nucleus. A mutation changing one of the phosphorylation sites to a glutamic acid resulted in the prolonged retention of the xnf7 protein in the cytoplasm until stages 9-10, well past the MBT. Additionally, a mutant form of xnf7 possessing a second nuclear localization signal at the COOH terminus was retained in the cytoplasm. This suggests that retention of xnf7 was not due to the masking of its NLS as is the case with NFkB and dorsal but was due to a novel anchoring mechanism in which the CRD interacts with an anchor protein. The CRD sequence is also found in another B-box zinc finger protein that is also retained in the cytoplasm until the MBT in the newt. Therefore, we believe that this may be an important mechanism whereby the function of a number of nuclear proteins is regulated during development.
Beg,
I kappa B interacts with the nuclear localization sequences of the subunits of NF-kappa B: a mechanism for cytoplasmic retention.
1992, Pubmed
Beg,
I kappa B interacts with the nuclear localization sequences of the subunits of NF-kappa B: a mechanism for cytoplasmic retention.
1992,
Pubmed
Bellini,
A putative zinc-binding protein on lampbrush chromosome loops.
1993,
Pubmed
Blank,
Cytoplasmic retention, DNA binding and processing of the NF-kappa B p50 precursor are controlled by a small region in its C-terminus.
1991,
Pubmed
Cornish,
Xlcaax-1 is localized to the basolateral membrane of kidney tubule and other polarized epithelia during Xenopus development.
1992,
Pubmed
,
Xenbase
Dreyer,
Differential accumulation of oocyte nuclear proteins by embryonic nuclei of Xenopus.
1987,
Pubmed
,
Xenbase
Etkin,
Replication, integration and expression of exogenous DNA injected into fertilized eggs of Xenopus laevis.
1984,
Pubmed
,
Xenbase
Etkin,
Distribution, expression and germ line transmission of exogenous DNA sequences following microinjection into Xenopus laevis eggs.
1987,
Pubmed
,
Xenbase
Forbes,
Structure and function of the nuclear pore complex.
1992,
Pubmed
,
Xenbase
Freemont,
The RING finger. A novel protein sequence motif related to the zinc finger.
1993,
Pubmed
Gannon,
Protein synthesis required to anchor a mutant p53 protein which is temperature-sensitive for nuclear transport.
1991,
Pubmed
Ghosh,
Activation in vitro of NF-kappa B by phosphorylation of its inhibitor I kappa B.
1990,
Pubmed
Govind,
Dorsoventral pattern formation in Drosophila: signal transduction and nuclear targeting.
1991,
Pubmed
Henkel,
Intramolecular masking of the nuclear location signal and dimerization domain in the precursor for the p50 NF-kappa B subunit.
1992,
Pubmed
Hennekes,
Phosphorylation on protein kinase C sites inhibits nuclear import of lamin B2.
1993,
Pubmed
Horton,
Gene splicing by overlap extension: tailor-made genes using the polymerase chain reaction.
1990,
Pubmed
Hunt,
Cytoplasmic anchoring proteins and the control of nuclear localization.
1989,
Pubmed
Jans,
p34cdc2-mediated phosphorylation at T124 inhibits nuclear import of SV-40 T antigen proteins.
1991,
Pubmed
Kerr,
The rel-associated pp40 protein prevents DNA binding of Rel and NF-kappa B: relationship with I kappa B beta and regulation by phosphorylation.
1991,
Pubmed
Kieran,
The DNA binding subunit of NF-kappa B is identical to factor KBF1 and homologous to the rel oncogene product.
1990,
Pubmed
Lenardo,
NF-kappa B: a pleiotropic mediator of inducible and tissue-specific gene control.
1989,
Pubmed
Li,
Xenopus nuclear factor 7 (xnf7) possesses an NLS that functions efficiently in both oocytes and embryos.
1993,
Pubmed
,
Xenbase
Miller,
The nuclear-cytoplasmic distribution of the Xenopus nuclear factor, xnf7, coincides with its state of phosphorylation during early development.
1991,
Pubmed
,
Xenbase
Miller,
xlgv7: a maternal gene product localized in nuclei of the central nervous system in Xenopus laevis.
1989,
Pubmed
,
Xenbase
Moll,
The role of phosphorylation and the CDC28 protein kinase in cell cycle-regulated nuclear import of the S. cerevisiae transcription factor SWI5.
1991,
Pubmed
Moll,
Two distinct mechanisms alter p53 in breast cancer: mutation and nuclear exclusion.
1992,
Pubmed
Newport,
A major developmental transition in early Xenopus embryos: I. characterization and timing of cellular changes at the midblastula stage.
1982,
Pubmed
,
Xenbase
Nigg,
Nuclear import-export: in search of signals and mechanisms.
1991,
Pubmed
Picard,
Two signals mediate hormone-dependent nuclear localization of the glucocorticoid receptor.
1987,
Pubmed
Pratt,
Control of steroid receptor function and cytoplasmic-nuclear transport by heat shock proteins.
1992,
Pubmed
Reddy,
A unique bipartite cysteine-histidine motif defines a subfamily of potential zinc-finger proteins.
1991,
Pubmed
,
Xenbase
Reddy,
The cloning and characterization of a maternally expressed novel zinc finger nuclear phosphoprotein (xnf7) in Xenopus laevis.
1991,
Pubmed
,
Xenbase
Reddy,
A novel zinc finger coiled-coil domain in a family of nuclear proteins.
1992,
Pubmed
Roth,
A gradient of nuclear localization of the dorsal protein determines dorsoventral pattern in the Drosophila embryo.
1989,
Pubmed
Rushlow,
The graded distribution of the dorsal morphogen is initiated by selective nuclear transport in Drosophila.
1989,
Pubmed
Schmitz,
Proteins controlling the nuclear uptake of NF-kappa B, Rel and dorsal.
1991,
Pubmed
Silver,
How proteins enter the nucleus.
1991,
Pubmed
Steward,
Relocalization of the dorsal protein from the cytoplasm to the nucleus correlates with its function.
1989,
Pubmed
Whiteside,
Signal transduction and nuclear targeting: regulation of transcription factor activity by subcellular localisation.
1993,
Pubmed
