Brassinosteroids are plant hormones used in many processes including growth, immunity and the development of plants. This pathway depicts brassinosteroid synthesis in a cell from the species Arabidopsis thaliana, or mouse-ear cress. This species in particular has provided recent insight on brassinosteroid’s role in plant growth through molecular genetics. The pathway begins with campesterol, a compound created through steroid biosynthesis. As brassinosteroid synthesis moves along, compounds react inter-connectedly with many different proteins, to finally create 26-hydroxybrassinolide. Some of the proteins commonly used in this pathway include cytochrome P450 90B1, cytochrome P450 90D2, cytochrome P450 85A2 and 3-epi-6-deoxocathasterone 23-monooxygenase CYP90D1. These proteins are found in various locations throughout the plant cell, such as the membrane, the endoplasmic reticulum, and the mitochondrial matrix. The proteins that a dark green indicate reactions taking place in the plasma membrane.

Brassinosteroid Synthesis References