Biology 1002B Lecture 16: Cycle 8 Lecture 16
Document Summary
Gene expression regulates changes that occur through determination and differentiation. Molecular mechanisms involved in determination and differentiation usually depend on regulatory genes that encode regulatory proteins that control the expression of other genes. Production of skeletal muscle cells from somites in mammals. Somites blocks of mesoderm cells that form along both sides of the notochord. Under genetic control, some cells of each somite differentiate into skeletal muscle cells. Paracrine signalling from nearby cells induces somite cells to express the master regulatory gene, myod: product of myod is the transcription factor myod. Myod brings about determination, converting cells to myoblasts (undifferentiated muscle cells) Gene control of pattern formation: forming a body. As part of the signals guiding differentiation, cells receive positional information that tells them where they are in the embryo. Vital to pattern formation arrangement of body structures in their proper 3d relationship. Laid down primarily as concentration gradients of regulatory molecules produced by genetic control.