BIOL303 Lecture Notes - Lecture 3: Transforming Growth Factor Beta, Syncytium, Blastomere
Document Summary
Biol 303 lecture set #3: endocrine signalling is signals that act from a distance, like hormones in the circulatory system. Paracrine signalling is the localized production of paracrine factors, soluble proteins, peptides, or glycoproteins secreted into the extracellular space. Instructive induction is when the responding signal from the inducing cell is necessary for initiating new gene expression in the responding cell. Permissive induction is when the responding tissue has already been specified and needs only an environment that allows the expression of these traits: an example of an inductive interaction that shows regional specificity is in chicks. Cells from different regions of the dermis (mesenchyme) are recombined with the epidermis (epithelium), the type of cutaneous structure made by the epidermal epithelium is determined by the original source of the mesenchyme. Paracrine interaction is proteins synthesized by one cell can diffuse over small distance to induce changes in neighbouring cells.
