caa a22 4500 475817524 CHVBK 20180406123813.0 cr unu---uuuuu 170329e20000401xx s 000 0 eng 10.1007/s004970050196 doi (NATIONALLICENCE)springer-10.1007/s004970050196 Ubiquitin and ubiquitin-conjugated proteins in the olive ( olea europaea l.) pollen [Elektronische Daten] [J. D. Alché, R. Butowt, A. J. Castro, M. I. Rodríguez-García] Abstract : A study of free ubiquitin and ubiquitinated proteins has been carried out in olive (Olea europaea L.) during the late stages of pollen development and during in-vitro pollen hydration. As described in relatively few plant species, immunoblot experiments carried out using crude protein extracts have shown a reduction in the free ubiquitin level taking place during the mature pollen stage. This reduction does not coincide with a parallel reduction in the level of the corresponding transcripts, as detected by RT-PCR analysis, suggesting the existence of a post-transcriptional regulatory mechanism. Relatively high levels of free ubiquitin are quickly restored upon in-vitro pollen hydration. TEM immunocytochemical localisation of ubiquitin-conjugated compounds in the mature pollen grain showed the antibodies bound to the cytoplasm, the chromatin and the nucleolus of the vegetative and generative cells. Within the cytoplasm, labelling was concentrated in the cytosol, the endoplasmic reticulum membranes and minuscule vesicles associated to the Golgi apparatus. The fibrillar material adhering to the exine, and probably derived from the tapetum, also showed gold particles. Lipid bodies, aperture regions, mitochondria, the intine and the cell wall were devoid of labelling. The changes observed throughout pollen development, as well as the specific localisation, reflect the involvement of the ubiquitin-mediated degradative pathway in regulation of pollen metabolism. Springer-Verlag Berlin Heidelberg, 2000 Key words Ubiquitin nationallicence Ubiquitin-conjugated proteins nationallicence mRNA nationallicence Pollen olive tree nationallicence Alché J. D. Departamento de Bioquímica, Biología Celular y Molecular de Plantas, Estación Experimental del Zaidín, CSIC, Profesor Albareda 1, E-18008 Granada, Spain, e-mail:mirbicep@eez.csic.es Tel.: +34-958-121011, Fax: +34 958 129600, ES aut Butowt R. Departamento de Bioquímica, Biología Celular y Molecular de Plantas, Estación Experimental del Zaidín, CSIC, Profesor Albareda 1, E-18008 Granada, Spain, e-mail:mirbicep@eez.csic.es Tel.: +34-958-121011, Fax: +34 958 129600, ES aut Castro A. J. aut Rodríguez-García M. I. aut https://doi.org/10.1007/s004970050196 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s004970050196 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Alché J. D. Departamento de Bioquímica, Biología Celular y Molecular de Plantas, Estación Experimental del Zaidín, CSIC, Profesor Albareda 1, E-18008 Granada, Spain, e-mail:mirbicep@eez.csic.es Tel.: +34-958-121011, Fax: +34 958 129600, ES aut NATIONALLICENCE 700 1- Butowt R. Departamento de Bioquímica, Biología Celular y Molecular de Plantas, Estación Experimental del Zaidín, CSIC, Profesor Albareda 1, E-18008 Granada, Spain, e-mail:mirbicep@eez.csic.es Tel.: +34-958-121011, Fax: +34 958 129600, ES aut NATIONALLICENCE 700 1- Castro A. J. aut NATIONALLICENCE 700 1- Rodríguez-García M. I. aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer