Abstract
Immunofluorescent reactions specific for distinct chromosomal structures are obtained by using antiserum to oocyte proteins. Antisera diluted more than 1000-fold are used to localize proteins associated with RNA transcripts in unfixed lampbrush chromosomes of Triturus cristatus carnifex. Of the several protein components of nuclear RNP, at least some are bound to all chromosome transcripts and may form the basis of the regular 20 nm beads characteristic of the RNP chain. On the other hand some proteins are peculiar to a restricted number of loci (loops). For example, a nuclear RNP protein in the size range 30–35,000 daltons is bound to the transcripts of only several of the many thousands of loops. Also, the two highly basic proteins of a cytoplasmic 40S particle have a special chromosomal location, one with the 5S locus, the other with putative tRNA loops. In these instances it is likely that there is recognition by proteins of particular RNA nucleotide sequences, or their resulting secondary structure, as they are generated. The specific immunostaining of distinct loops can be used not only to identify the genetic sequences being transcribed but also to give information on the pattern of transcription and processing. In contrast to the RNA-binding proteins, most of the chromosomal histone is seen, by immunofluorescence, to be localized in chromatin which is condensed in chromomeric structures and not active in transcription.
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Alfageme, C.R., Rudkin, G.T., Cohen, L.H.: Locations of chromosomal proteins in polytene chromosomes. Proc. nat. Acad. Sci. (Wash.) 73, 2038–2042 (1976)
Beyer, A.L., Christensen, M.E., Walker, B.W., LeStourgeon, W.M.: Identification and charterization of the packaging proteins of core 40S hnRNP particles. Cell 11, 127–138 (1977)
Desai, L.S., Pothier, L., Foley, G.E., Adams, R.A.: Immunofluorescent labelling of chromosomes with antisera to histories and histone fractions. Exp. Cell Res. 70, 468–471 (1972)
Ford, P.J.: Non-coordinated accumulation and synthesis of 5S ribonucleic acid by ovaries of Xenopus laevis. Nature (Lond.) 233, 561–564 (1971)
Izawa, M., Allfrey, V.G., Mirsky, A.E.: Composition of the nucleus and chromosomes in the lampbrush stage of the newt oocyte. Proc. nat. Acad. Sci. (Wash.) 50, 811–817 (1963)
Kish, V.M., Pederson, T.: Heterogeneous nuclear RNA secondary structure: oligo(U) sequences base-paired with poly(A) and their possible role as binding sites for heterogeneous nuclear RNA-specific proteins. Proc. nat. Acad. Sci. (Wash.) 74, 1426–1430 (1977)
Laemmli, U.K.: Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature (Lond.) 227, 680–685 (1970)
Leoning, U.E.: The determination of the molecular weight of ribonucleic acid by polyacrylamide gel electrophoresis. Biochem. J. 113, 131–138 (1969)
LeStourgeon, W.M., Forer, A., Yang, Y-Z., Bertram, J.S., Rusch, H.P.: Contractile proteins: major components of nuclear and chromosome non-histone proteins. Biochim. biophys. Acta (Amst.) 379, 529–552 (1975)
Mairy, M., Denis, H.: Recherches biochimique sur l'oogenèse. 1. Synthèse et accumulation du RNA pendant l'oogenèse du crapaud sud-africain Xenopus laevis. Develop. Biol. 24, 143–165 (1971)
Malcolm, D.B., Sommerville, J.: The structure of chromosome-derived ribonucleoprotein in oocytes of Triturus cristatus carnifex. Chromosoma (Berl.) 48, 137–158 (1974)
Malcolm, D.B., Sommerville, J.: The structure of nuclear ribonucleoprotein of amphibian oocytes. J. Cell Sci. 24, 143–165 (1977)
Miller, O.L., Hamkalo, B.A.: Visualization of RNA synthesis on chromosomes. Int. Rev. Cytol. 33, 1–25 (1972)
Old, R.W., Callan, H.G., Gross, K.W.: Localization of histone gene transcripts in newt lampbrush chromosomes by in situ hybridization. J. Cell Sci. 27, 57–79 (1977)
Parker, C.S., Roeder, R.G.: Selective and accurate transcription of the Xenopus laevis 5 S RNA genes in isolated chromatin by purified RNA polymerase III. Proc. nat. Acad. Sci. (Wash.) 74, 44–48 (1977)
Pukkila, P.J.: Identification of the lampbrush chromosome loops which transcribe 5 S ribosomal RNA in Notophthalmus (Triturus) viridescens. Chromosoma (Berl.) 53, 71–89 (1975)
Radola, B.J.: Isoelectric focusing in layers of granulated gels. II. Preparative isoelectric focusing. Biochim. biophys. Acta (Amst.) 386, 181–195 (1974)
Scheer, U., Franke, W.W., Trendelenburg, M.F., Spring, H.: Classification of loops of lampbrush chromosomes according to the arrangement of transcriptional complexes. J. Cell Sci. 22, 503–520 (1976)
Scott, S.E.M., Sommerville, J.: Location of nuclear proteins on the chromosomes of newt oocytes. Nature (Lond.) 250, 680–682 (1974)
Silver, L.M., Elgin, S.C.R.: A method for determination of the in situ distribution of chromosomal proteins. Proc. nat. Acad. Sci. (Wash.) 73, 423–427 (1976)
Sommerville, J.: Ribonucleoprotein particles derived from the lampbrush chromosomes of newt oocytes. J. molec. Biol. 78, 487–503 (1973)
Sommerville, J., Malcolm, D.B.: Transcription of genetic information in amphibian oocytes. Chromosoma (Berl.) 55, 183–208 (1976)
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Sommerville, J., Crichton, C. & Malcolm, D. Immunofluorescent localization of transcriptional activity on lampbrush chromosomes. Chromosoma 66, 99–114 (1978). https://doi.org/10.1007/BF00295133
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DOI: https://doi.org/10.1007/BF00295133