scholarly journals Phloem Companion Cell-Specific Transcriptomic and Epigenomic Analyses Identify MRF1, a Regulator of Flowering

2019 ◽  
Vol 31 (2) ◽  
pp. 325-345 ◽  
Author(s):  
Yuan You ◽  
Aneta Sawikowska ◽  
Joanne E. Lee ◽  
Ruben M. Benstein ◽  
Manuela Neumann ◽  
...  
Keyword(s):  
Companion Cell

Elemental Analysis of Phloem Tissue in Lemna Minor Root Tips

1980 ◽  
Vol 38 ◽  
pp. 798-799
Author(s):  
Patrick Echlin ◽  
Thomas Hayes ◽  
Clifford Lai ◽  
Greg Hook
Keyword(s):  
Vascular Tissue ◽  
Lemna Minor ◽  
Atomic Weight ◽  
Companion Cell ◽  
Root Tips ◽  
Phloem Tissue ◽  
Cell Stage ◽  
Phloem Parenchyma ◽  
Parenchyma Cells ◽  
Xylem Element

Studies (1—4) have shown that it is possible to distinguish different stages of phloem tissue differentiation in the developing roots of Lemna minor by examination in the transmission, scanning, and optical microscopes. A disorganized meristem, immediately behind the root-cap, gives rise to the vascular tissue, which consists of single central xylem element surrounded by a ring of phloem parenchyma cells. This ring of cells is first seen at the 4-5 cell stage, but increases to as many as 11 cells by repeated radial anticlinal divisions. At some point, usually at or shortly after the 8 cell stage, two phloem parenchyma cells located opposite each other on the ring of cells, undergo an unsynchronized, periclinal division to give rise to the sieve element and companion cell. Because of the limited number of cells involved, this developmental sequence offers a relatively simple system in which some of the factors underlying cell division and differentiation may be investigated, including the distribution of diffusible low atomic weight elements within individual cells of the phloem tissue.

scholarly journals THE FINE STRUCTURE AND DEVELOPMENT OF THE COMPANION CELL OF THE PHLOEM OF ACER PSEUDOPLATANUS

1965 ◽  
Vol 24 (1) ◽  
pp. 117-128 ◽  
Author(s):  
F. B. P. Wooding ◽  
D. H. Northcote
Keyword(s):  
Endoplasmic Reticulum ◽  
Sieve Tube ◽  
Acer Pseudoplatanus ◽  
Sieve Plate ◽  
Wheat Grain ◽  
Companion Cell ◽  
Large Nucleus ◽  
Cell Organelles ◽  
Phloem Tissue ◽  
Aleurone Cells

At maturity the companion cell of the phloem of the sycamore Acer pseudoplatanus has a large nucleus, simple plastids closely sheathed with rough endoplasmic reticulum, and numerous mitochondria. The cytoplasm contains numerous ribosomes, resulting in a very electron-opaque cytoplasm after permanganate fixation. Bodies similar to the spherosomes of Frey-Wyssling et al. (4) are collected in clusters and these also contain bodies of an unidentified nature similar to those found by Buttrose (1) in the aleurone cells of the wheat grain. The pores through the wall between the companion cell and sieve tube are complex and develop from a single plasmodesma. Eight to fifteen plasmodesmata on the companion cell side communicate individually with a cavity in the centre of the wall which is linked to the sieve tube by a single pore about twice the diameter of an individual plasmodesma. This pore is lined with material of an electron opacity equivalent to that of material bounding the sieve plate pores. The development of the cell organelles, the possible role played in the phloem tissue by the companion cell, and the function of the complex pores contained in its wall are discussed.

scholarly journals A Companion Cell–Dominant and Developmentally Regulated H3K4 Demethylase Controls Flowering Time in Arabidopsis via the Repression of FLC Expression

PLoS Genetics ◽  
2012 ◽  
Vol 8 (4) ◽  
pp. e1002664 ◽  
Author(s):  
Hongchun Yang ◽  
Zhifu Han ◽  
Ying Cao ◽  
Di Fan ◽  
Hong Li ◽  
...  
Keyword(s):  
Flowering Time ◽  
Companion Cell ◽  
Developmentally Regulated

Plasma membrane localization of the type I H+-PPase AVP1 in sieve element–companion cell complexes from Arabidopsis thaliana

Plant Science ◽  
2011 ◽  
Vol 181 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Julio Paez-Valencia ◽  
Araceli Patron-Soberano ◽  
Alejandra Rodriguez-Leviz ◽  
Jonathan Sanchez-Lares ◽  
Concepcion Sanchez-Gomez ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Plasma Membrane ◽  
Sieve Element ◽  
Membrane Localization ◽  
Type I ◽  
Companion Cell ◽  
Cell Complexes ◽  
Plasma Membrane Localization
Sign in / Sign up

Export Citation Format

Share Document