CYP703A2 (CYTOCHROME P450, FAMILY 703, SUBFAMILY A, POLYPEPTIDE 2)
member of CYP703A CYP703A2 is expressed specifically in anthers of land plants, catalyzing the in-chain hydroxylation at the C-7 position of medium-chain saturated fatty acids (lauric acid in-chain hydroxylase) which is involved in pollen development (sporopollenin synthesis).
Responsible for the synthesis of callose deposited at the primary cell wall of meiocytes, tetrads and microspores. Required for exine formation during microgametogenesis and for pollen viability. Highest expression in meiocytes, tetrads, microspores and mature pollen.
Sporophytic factor controlling anther and pollen development. Mutants fail to make functional pollen;pollen degeneration occurs after microspore release and the tapetum also appears abnormally vacuolated. Similar to PHD-finger motif transcription factors.
The process whose specific outcome is the progression of the pollen grain over time, from its formation to the mature structure. The process begins with the meiosis of the microsporocyte to form four haploid microspores. The nucleus of each microspore then divides by mitosis to form a two-celled organism, the pollen grain, that contains a tube cell as well as a smaller generative cell. The pollen grain is surrounded by an elaborate cell wall. In some species, the generative cell immediately divides again to give a pair of sperm cells. In most flowering plants, however this division takes place later, in the tube that develops when a pollen grain germinates.
A process that is carried out at the cellular level which results in the assembly, arrangement of constituent parts, or disassembly of external structures that lie outside the plasma membrane and surround the entire cell.
