Question

What are cyclins and CDKs? Describe how both these types of proteins are regulated, based on five ways to control proteins.

Answer 1

Two groups of proteins are responsible for the progress of cell through various checkpoints.They are cyclin and CDKs.

Cyclins are family of regulatory proteins that control the progression of cell cycle.When cycline are synthesized ,they act as an activatimg protein and bind to CDKs forming a cyclin cdkS complex which act as a signal to the cell to pass to the next cell cycle phase.

CDKs are the families of protein kinases and their role is to regulate cell cycle and are also involved in regulating transcription,mRNA processing and the differentiation of nervecells.

Cyclin and CDKs regulate the cell cycle both by promoting activities of their respective stage.Cyclins regulate the cell cycle only when the are tightly bound to cdks.CDKs adds negatievly charged phosphate groups to other molecules in a process called phosphorylation.The proteins phosphorylated by cdks are involved in advancing the cell to next phase.Through this CDKs signal the cells that is ready to pass into the next stage of the cell cycle.The concentration of cyclin fluctuates and levels of cdks proteins are relatievly stable through out the cycle.