Small nuclear ribonucleoproteins and heterogeneous nuclear ribonucleoproteins in the amphibian germinal vesicle: loops, spheres, and snurposomes

doi:10.1083/jcb.113.3.465

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Small nuclear ribonucleoproteins and heterogeneous nuclear ribonucleoproteins in the amphibian germinal vesicle: loops, spheres, and snurposomes

ZA Wu, C Murphy, HG Callan and JG Gall
Department of Embryology, Carnegie Institution, Baltimore, Maryland 21210.

We have examined the distribution of snRNPs in the germinal vesicle (GV) of frogs and salamanders by immunofluorescent staining and in situ nucleic acid hybridization. The major snRNAs involved in pre-mRNA splicing (U1, U2, U4, U5, and U6) occur together in nearly all loops of the lampbrush chromosomes, and in hundreds to thousands of small granules (1-4 microns diameter) suspended in the nucleoplasm. The loops and granules also contain several antigens that are regularly associated with snRNAs or spliceosomes (the Sm antigen, U1- and U2- specific antigens, and the splicing factor SC35). A second type of granule, often distinguishable by morphology, contains only U1 snRNA and associated antigens. We propose the term "snurposome" to describe the granules that contain snRNPs ("snurps"). Those that contain only U1 snRNA are A snurposomes, whereas those that contain all the splicing snRNAs are B snurposomes. GVs contain a third type of snRNP granule, which we call the C snurposome. C snurposomes range in size from less than 1 micron to giant structures greater than 20 microns in diameter. Usually, although not invariably, they have B snurposomes on their surface. They may also contain from one to hundreds of inclusions. Because of their remarkably spherical shape, C snurposomes with their associated B snurposomes have long been referred to as spheres or sphere organelles. Most spheres are free in the nucleoplasm, but a few are attached to chromosomes at specific chromosome loci, the sphere organizers (SOs). The relationship of sphere organelles to other snRNP- containing structures in the GV is obscure. We show by immunofluorescent staining that the lampbrush loops and B snurposomes also react with antibodies against heterogeneous nuclear ribonucleoproteins (hnRNPs). Transcription units on the loops are uniformly stained by anti-hnRNP and anti-snRNP antibodies, suggesting that nascent transcripts are associated with hnRNPs and snRNPs along their entire length, perhaps in the form of a unitary hnRNP/snRNP particle. That B snurposomes contain so many components involved in pre- mRNA packaging and processing suggests that they may serve as sites for assembly and storage of hnRNP/snRNP complexes destined for transport to the nascent transcripts on the lampbrush chromosome loops.
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CUSTODIO, N., CARVALHO, C., CONDADO, I., ANTONIOU, M., BLENCOWE, B. J., CARMO-FONSECA, M. (2004). In vivo recruitment of exon junction complex proteins to transcription sites in mammalian cell nuclei. RNA 10: 622-633 [Abstract] [Full Text]
Doyle, M., Jantsch, M. F. (2003). Distinct in vivo roles for double-stranded RNA-binding domains of the Xenopus RNA-editing enzyme ADAR1 in chromosomal targeting. JCB 161: 309-319 [Abstract] [Full Text]
Handwerger, K. E., Murphy, C., Gall, J. G. (2003). Steady-state dynamics of Cajal body components in the Xenopus germinal vesicle. JCB 160: 495-504 [Abstract] [Full Text]
Gall, J. G., Bellini, M., Wu, Z.'a., Murphy, C. (1999). Assembly of the Nuclear Transcription and Processing Machinery: Cajal Bodies (Coiled Bodies) and Transcriptosomes. Mol. Biol. Cell 10: 4385-4402 [Abstract] [Full Text]
Bellini, M., Gall, J. G. (1999). Coilin Shuttles between the Nucleus and Cytoplasm In Xenopus Oocytes. Mol. Biol. Cell 10: 3425-3434 [Abstract] [Full Text]
Narayanan, A., Speckmann, W., Terns, R., Terns, M. P. (1999). Role of the Box C/D Motif in Localization of Small Nucleolar RNAs to Coiled Bodies and Nucleoli. Mol. Biol. Cell 10: 2131-2147 [Abstract] [Full Text]
Jolly, C., Vourc'h, C., Robert-Nicoud, M., Morimoto, R. I. (1999). Intron-independent Association of Splicing Factors with Active Genes. JCB 145: 1133-1143 [Abstract] [Full Text]
Eckmann, C. R., Jantsch, M. F. (1999). The RNA-editing Enzyme ADAR1 Is Localized to the Nascent Ribonucleoprotein Matrix on Xenopus Lampbrush Chromosomes but Specifically Associates with an Atypical Loop. JCB 144: 603-615 [Abstract] [Full Text]
Abbott, J., Marzluff, W. F., Gall, J. G. (1999). The Stem-Loop Binding Protein (SLBP1) Is Present in Coiled Bodies of the Xenopus Germinal Vesicle. Mol. Biol. Cell 10: 487-499 [Abstract] [Full Text]
Lange, T. S., Ezrokhi, M., Borovjagin, A. V., Rivera-León, R., North, M. T., Gerbi, S. A. (1998). Nucleolar Localization Elements of Xenopus laevis U3 Small Nucleolar RNA. Mol. Biol. Cell 9: 2973-2985 [Abstract] [Full Text]
Bellini, M., Gall, J. G. (1998). Coilin Can Form a Complex with the U7 Small Nuclear Ribonucleoprotein. Mol. Biol. Cell 9: 2987-3001 [Abstract] [Full Text]
Lamond, A. I., Earnshaw, W. C. (1998). Structure and Function in the Nucleus. Science 280: 547-553 [Abstract] [Full Text]
Gall, J. G., Murphy, C. (1998). Assembly of Lampbrush Chromosomes from Sperm Chromatin. Mol. Biol. Cell 9: 733-747 [Abstract] [Full Text]
Eckmann, C. R., Jantsch, M. F. (1997). Xlrbpa, a Double-stranded RNA-binding Protein Associated with Ribosomes and Heterogeneous Nuclear RNPs. JCB 138: 239-253 [Abstract] [Full Text]
Dirks, R., de Pauw, E., Raap, A. (1997). Splicing factors associate with nuclear HCMV-IE transcripts after transcriptional activation of the gene, but dissociate upon transcription inhibition: evidence for a dynamic organization of splicing factors. J. Cell Sci. 110: 515-522 [Abstract]
Alzhanova-Ericsson, A T, Sun, X, Visa, N, Kiseleva, E, Wurtz, T, Daneholt, B (1996). A protein of the SR family of splicing factors binds extensively to exonic Balbiani ring pre-mRNA and accompanies the RNA from the gene to the nuclear pore.. Genes Dev. 10: 2881-2893 [Abstract]
Puvion-Dutilleul, F, Besse, S, Chan, E., Tan, E., Puvion, E (1995). p80-coilin: a component of coiled bodies and interchromatin granule-associated zones. J. Cell Sci. 108: 1143-1153 [Abstract]
Beven, A., Simpson, G., Brown, J., Shaw, P. (1995). The organization of spliceosomal components in the nuclei of higher plants. J. Cell Sci. 108: 509-518 [Abstract]
Ochs, R., Stein, T., Tan, E. (1994). Coiled bodies in the nucleolus of breast cancer cells. J. Cell Sci. 107: 385-399 [Abstract]
Wassarman, K M, Steitz, J A (1993). Association with terminal exons in pre-mRNAs: a new role for the U1 snRNP?. Genes Dev. 7: 647-659 [Abstract]
Wu, Z., Murphy, C., Wu, C.-H.H., Tsvetkov, A., Gall, J.G. (1993). Snurposomes and Coiled Bodies. Cold Spring Harb Symp Quant Biol 58: 747-754 [Abstract]
Zahler, A M, Lane, W S, Stolk, J A, Roth, M B (1992). SR proteins: a conserved family of pre-mRNA splicing factors.. Genes Dev. 6: 837-847 [Abstract]
Huang, S, Spector, D L (1991). Nascent pre-mRNA transcripts are associated with nuclear regions enriched in splicing factors.. Genes Dev. 5: 2288-2302 [Abstract]