Elaioplasts are one of the three possible forms of , sometimes broadly referred to as such.
Description
Like most leucoplasts, elaioplasts are non-pigmented organelles capable of alternating between the different forms of . The elaioplast specifically is primarily responsible for the storage and metabolism of lipids,[ Typically, they appear as small, rounded organelles filled by oil droplets.][ Lipids found inside elaioplasts mirror those synthesized by , chiefly Triglyceride and sterol esters, which cluster into the droplets visible by microscope.][ As for their other components, elaioplasts also contain plastoglobuli associated proteins such as , a protein family believed to be retained from the ancestors of plastids.][ Alongside the tapetosomes (clusters of oil and proteins produced by the endoplasmic reticulum), elaioplasts are frequently found in the tapetum of angiosperm anthers, where their products, oil from the plastid and protein from the tapetosome, are used to form the pollen coat of developing Pollen.][ Following the maturation of pollen grains, these organelles are degraded and released into the anther loculus.][ Found also in oilseeds, elaioplasts in this group provide lipids to be converted into carbohydrates which will serve as fuel in the embryo's germination.][ Citrus specimens have been shown to have especially high amounts of elaioplasts in their fruit peels, where they are essential to the production of terpenes.][
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Development
Within the plant, elaioplasts, as well as all other plastids, arise from proplastids in the dividing portion of the stem (meristem). These proplastids have not yet differentiated and, as such, can develop into any variety of known plastids, determined by the tissues they are present in.
Origin and inheritance
Plastids are hypothesized to have originated with an Endosymbiont event between an ancient eukaryote and cyanobacterial ancestor more than 1 billion years ago, where the bacteria was engulfed by the other and retained where it served as the metabolic center for photosynthesis.[
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Like most plastids, elaioplasts reproduce through binary fission independent from the division of the parent cell, a feature indicative of their bacterial ancestry.[ This fission occurs just before cytokinesis, with the products then being transported to the daughter cells as a component of the cytoplasm.][
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As a result of the ability to inter-convert between other types of the plastid family, elaioplasts share the same plastome(plastid genome) with all other plastids and are predominately inherited maternally in angiosperms.
See also
