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Start Over Creator Selga, T.

1. Plastid-nuclear complexes in the photosynthesizing cells from their mitosis up to programmed death

Creator:
Selga, T., Selga, M., and Ozoliņa, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, photosynthesis, chloroplasts, Nicotiana tabaccum, nuclei, programmed cell death, 2, and 581
Language:
Multiple languages
Description:
Permanent plastid-nuclear complexes (PNCs) exist in tobacco cells from their mitosis up to programmed cell death (PCD). PNCs in senescing cells of tobacco leaves were typical by enclosure of peroxisomes and mitochondria among chloroplasts which were in contact with nucleus. Such a complex position provides simultaneous interaction of these organelles and direct regulation of metabolism and PCD avoiding the cytosol. and T. Selga, M. Selga, A. Ozoliņa.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. The synapse-like interaction between chloroplast, dictyosome, and other cell compartments during increased ethylene production in leaves of rye (Secale cereale L.)

Creator:
Selga, T. and Selga, M.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
electron microscopy, endoplasmic reticulum, ethephon, Golgi appaaratus, intercellular signalling, and mitochondrion
Language:
Multiple languages
Description:
Rye (Secale cereale L.) plants were treated with an ethylene releaser ethephon (2-chloroethylphosphonic acid) in concentration of 4×10-2 M. We studied electron microscopically, if and how chloroplasts interact with well-documented sites of ethylene production/binding, i.e., with endoplasmic reticulum, dictyosomes, mitochondria, plasma membrane, and tonoplast. During the sharp increase of ethylene synthesis in mesophyll cells of rye leaves, the direct local continguity of chloroplast envelope or envelope protrusions with the above mentioned cell compartments was typical. Moreover, a large number and diversity of versatile chloroplast-dictyosome associations were conspicuous, in which both the chloroplast and each cisterna of dictyosome were capable to exo/endocytosis. The dictyosomes were directed towards the chloroplasts, plasma membrane, or tonoplast both with cis-face, trans-face, or with the rim, they could change their direction or shut up the trans-face, developing simultaneously several flexible chains of vesicular dispatches among chloroplasts and some other cell compartments. This reflects interaction of protein/ethylene producing, photosynthesising, DNA containing compartments, and regulated action of lysosomal system. Structural contacts and vesicular transport among compartments of symplastic system equalises concentrations of H+, Ca2+, etc. ions, as well as provide connection with an apoplast. We propose that ethylene functions in plant mesophyll cells are both as intra/intercellular signalling substance and as phytohormone that regulates gene expression in nuclei, chloroplasts, and mitochondria in a complicated synapse-like process and causes programmed death of leaves of the main stalks of rye for the sake of promoted growth of side shoots. and T. Selga, M. Selga.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public