Tag: Cell Biology

Plasmodesmata are plasma membrane-enclosed pores between cells that were initially described by Tangl in 1879 as ‘open communications’ between protoplasts of endosperm cells. These structures are regulated by callose deposition from the apoplast and play an important regulatory role in stress and…

Pollen tubes exhibit unidirectional, polar growth because vesicles carrying compounds required for growth  are selectively transported to the growing apex. The phosphoinositide PtdIns(4,5)P2 accumulates at the apex and  is thought to help with vesicle targeting. Helpel et al. showed that the lipid…

KATANIN is a AAA ATPase protein which, according to the most recent models, is able to track along microtubules (MTs) and sever emergent γ-TUBULIN and AUGMIN-nucleated MTs. This severing event occurs at MT cross-over areas, particularly where there are MT lattice defects, promoting disassembly of unfavorable…

Plants repair wound sites through the formation of unorganized cell masses called calli, which can also serve as progenitors of new organs. Callus formation and organ regeneration often entail cell cycle re-entry of quiescent cells, which is achieved through the re-activation of core cell cycle regulators…

Plant glandular trichomes can store and secrete great amounts of volatile organic compounds (VOCs) that are important for a variety of processes, from development to interacting with herbivores. VOCs accumulate in specific extracellular spaces which can be subcuticular or intercellular. The active transport…

In order for a cell to expand, its volume needs to increase and the cell wall needs to loosen up. There are multiple processes resulting in cell wall loosening, but not all of them result in extension. Cosgrove differentiates different structural, mechanical and physiocochemical processes that lead to…

Pollen cells have a fascinating ability to transform from a small spherical cell to a very elongated shape known as the pollen tube (PT) during fertilization. Pollen cells must navigate through the female tissue, find an ovary, and burst to release the two sperm cell nuclei as well as the vegetative…

Both plants and animals have a sophisticated immune system comprising receptors to detect pathogen-encoded epitopes or virulence molecules. These receptors are programmed to recognize pathogen ligands which are rapidly evolving over an evolutionary time. However, the structural basis of ligand perception…