BIO230H1 Lecture Notes - Lecture 19: Quorum Sensing, Cellular Signalling, Endocrine System
42
BIO230H1 Full Course Notes
Verified Note
42 documents
Document Summary
Cells must communicate to develop & maintain multicellular organisms. Delay between unicellular organisms to multicellular organisms may be in part due to the time needed to evolve complex signalling systems. Cells can send out hundreds of different types of signalling molecules. Eg. proteins, small peptides, nucleotides, other small molecules, gases etc. Two ways it can receive the signal. Long synaptic signalling or endocrine signalling. Many components of the signalling pathways act like switches (ie. can be turned on/off) Eg. gain or loss of phosphate groups. ** switching off is just as important as switching on if the pathway is never turned off, then it won"t be able to send another signal ** Many components of signalling pathways interact like lego. Ie. add or subtract domains from a protein to change function over evolutionary time. Eg. there are many different sh2 and ptb domains; these different forms all bind to different specific phosphotyrosine (phosphorylated tyrosine) containing sequences.
