SPECTRIN-LIKE PROTEINS IN PLANT NUCLEI

• Published in: Cell biology international Vol. 24; no. 7; pp. 427 - 438
• Main Authors: De Ruijter, Norbert C.A., Ketelaar, Tijs, Blumenthal, Sonal S.D., Emons, Anne Mie C., Schel, Jan H.N.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Elsevier Ltd 01.01.2000; Blackwell Publishing Ltd
• Subjects: Cell Fractionation; Cell Nucleus - chemistry; CELL STRUCTURE; confocal laser scanning microscopy; EPS; GUISANTE; immunolocalization; Laboratorium voor Plantencelbiologie; Laboratory of Plant Cell Biology; Microfilament Proteins - analysis; Microfilament Proteins - immunology; Microscopy, Confocal; nuclear matrix; Nuclear Matrix - chemistry; Nuclear Proteins - analysis; Nuclear Proteins - immunology; NUCLEI; nucleus; PEAS; Pisum sativum; Pisum sativum - chemistry; Pisum sativum - ultrastructure; Plant Proteins - analysis; Plant Proteins - immunology; PLUMULES; POIS; PROTEINAS; PROTEINE; PROTEINS; spectrin; Spectrin - analysis; ULTRAESTRUCTURA; ULTRASTRUCTURE; nucleus; spectrin; immunolocalization; nuclear matrix; confocal laser scanning microscopy; Pisum sativum
• ISSN: 1065-6995; 1095-8355
• DOI: 10.1006/cbir.2000.0508

We analysed the presence and localization of spectrin-like proteins in nuclei of various plant tissues, using several anti-erythrocyte spectrin antibodies on isolated pea nuclei and nuclei in cells. Western blots of extracted purified pea nuclei show a cross-reactive pair of bands at 220–240kDa, typical for human erythrocyte spectrin, and a prominent 60kDa band. Immunolocalization by means of confocal laser scanning microscopy reveals spectrin-like proteins in distinct spots equally distributed in the nucleoplasm and over the nuclear periphery, independent of the origin of the anti-spectrin antibodies used. In some nuclei tracks of spectrin-like proteins are also observed. No signal is present in nucleoli. The amount and intensity of signal increases when nuclei were extracted, successively, with detergents, DNase I and RNase A, and high salt, indicating that the spectrin-like protein is associated with the nuclear matrix. The labelling is similar in nuclei of various plant tissues. These data are the first that show the presence and localization of spectrin-like epitopes in plant nuclei, where they may stabilize specific interchromatin domains.