Aleurone

[2] The aleurone layer surrounds the endosperm tissue of grass seeds and is morphologically and biochemically distinct from it.

In multicolored corn, anthocyanin pigments in the aleurone layer give the kernels a dark, bluish-black color.

[8] The development of the aleurone layer involves several periclinal, and anticlinal cell divisions and several steps of genetic regulation.

[9] The normal dek1 gene is needed in order to receive and respond to positional cues that determine the fate of aleurone cells during development.

[13] In addition, several hormones influence the development of the aleurone layer, including auxin, cytokinin, abscisic acid (ABA), and gibberellin (GA).

The aleurone layer performs a variety of functions to help maintain proper development of the seed.

[14] In addition, although the function is unclear, a certain class of hemoglobins is present in the outer layer of living cells including the aleurone tissue in barley and rice seeds.

[15] During seed germination, the plant embryo produces the hormone gibberellin which triggers the aleurone cells to release α-amylase for the hydrolysis of starch, proteases, and storage proteins into the endosperm.

Experiments conducted in the 1960s confirmed that in order for the aleurone layer to secrete starch-degrading enzymes, the embryo must be present.