A laticifer is a type of elongated secretory cell found in the leaves and/or stems of plants that produce latex and rubber as secondary metabolites. Laticifers may be divided into:
- Articulated laticifers, i.e., composed of a series of cells joined together, or
- Non-articulated laticifers, consisting of one long coenocytic cell.
Non-articulated laticifers begin their growth from the meristematic tissue of the embryo, termed the laticifer initial, and can exhibit continual growth throughout the lifetime of the plant.[1][2] Laticifer tubes have irregularly edged walls and a larger inner diameter than the surrounding parenchyma cells.[3] In the development of the cell, elongation occurs via karyokinesis and no cell plate develops resulting in coenocytic cells which extend throughout the plant.[2] These cells can reach up to tens of centimeters long and can be branched or unbranched. They are thought to have a role in wound healing and as defense against herbivory, as well as pathogen defense, and are often used for taxonomy.
Laticifers were first described by H. A. de Barry in 1877.
Laticifers are highly specialized cells which can produce a wide variety of proteins.[4] These proteins include enzymes functioning as proteinases and chitinases which help defend the producing plant against insects and other herbivores. In one study it was found that the presence and concentration of some proteins can differ greatly within the genus Croton relative to three species studied.[4]
https://en.wikipedia.org/wiki/Laticifer
Rickettsia is a gram-negative, rod-shaped, laticifer-inhibiting bacterium.[5] It is typically 0.8 to 1.6 µm long and 0.25 to 0.35 µm wide.[5] The bacteria are found within the sap of the plant.[5] The bacteria infect the plant's cells, destroying the cytoplasm along with its organelles, causing the cells to eventually collapse.[5]
https://en.wikipedia.org/wiki/Papaya_Bunchy_Top_Disease
Flora and fauna pathogenesis[edit]
Plant diseases have been associated with these Rickettsia-like organisms (RLOs):[16]
- Beet latent rosette RLO
- Citrus greening bacterium possibly this citrus greening disease
- Clover leaf RLO
- Grapevine infectious necrosis RLO
- Grapevine Pierce's RLO
- Grapevine yellows RLO
- Witch's broom disease on Larix spp.
- Peach phony RLO
- Papaya Bunchy Top Disease[17]
Infection occurs in nonhuman mammals; for example, species of Rickettsia have been found to afflict the South Americanguanaco, Lama guanacoe.[18]
https://en.wikipedia.org/wiki/Rickettsia
Ehrlichia is a genus of Rickettsiales bacteria that are transmitted to vertebrates by ticks. These bacteria cause the disease ehrlichiosis, which is considered zoonotic, because the main reservoirs for the disease are animals.
Ehrlichia species are obligately intracellular pathogens and are transported between cells through the host cell filopodia during initial stages of infection, whereas in the final stages of infection, the pathogen ruptures the host cell membrane.[2]
| Ehrlichia | |
|---|---|
 | |
| Ehrlichia ewingii | |
| Scientific classification | |
| Kingdom: | |
| Phylum: | |
| Class: | |
| Order: | |
| Family: | |
| Genus: | Ehrlichia |
| Species: | See text. |
| Synonyms | |
| |
https://en.wikipedia.org/wiki/Ehrlichia
SARS-CoV-2, the strain of coronavirus responsible for coronavirus disease 2019, produces filopodia in infected cells.[14]
https://en.wikipedia.org/wiki/Filopodia
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