BIOB51H3 Lecture Notes - Lecture 13: Snake Venom, Gene Duplication, Defensin
Document Summary
Evolution of gene networks & development-chapter 9 (lecture notes) Why venom: only a small subset of snakes use venom. Evolutionary changes in regulatory gene networks provide a great opportunity for facilitating adaptations. Regulatory mutation led to production of defensin gene in the mouth. Snake venom genes are recruited from genes expressed in many organs. Across nature: upstream section of dna includes the promoter region. Includes other regulatory sequences influences the transcription of dna. Repressor: protein that binds to a sequence of dna or rna inhibits the expression of one or more genes. Transcription factor: protein that binds to specific dna sequences turns all sequences on or off simultaneously. Complex adaptation: suite of coexpressed traits, experience selection for a common function, multiple components must be expressed together for the trait to function. Molecular blueprint for making spores in bacteria in complex. Adaptations: stress triggers this pathway, sporulation offers protection. Hierarchical gene organization controls development of animal embryos.
