Question

In organogenesis, many organs form through a process of receiprocal induction, where the development of two tissues are guided by information provided by each other. what does the process require? include competence, gene expression changes and paracrine signals.

Answer 1

Development of organs during embryogenesis depends on the surrounding cells and tissues. Cell cross talk with one another and produce certain chemical signals. These chemical signals will indice the cells to develop in certain manner. Such an interaction between two or more cells or tissues is called induction. When both tissues are inducing one another, it is called reciprocal induction.

The tissue that produces a signal which changes the bahaviour of another tissue is called inducer and the tissue which responds is called responder. The responder should be able to receive the signal and respond accordigly. It is called competence. For a cell to respond , it neds certain proteins or factors making it competent to receive the signal. These protein factors acting as the competent molecules is needed only for a responder not for an inducer.

Inducers are proteins which will activate the transcription factors. When the inducers are produced by the cells, a competent factor is synthesized in the cells to respond to the inducer. These competent factors allow the binding to certain regions in the DNA to start transcription and translation resulting expression of the genes. Such a cell cell signalling is also called paracrine signalling.It is the signalling process occuring between the neighbouring cells.

During the embryonic development, the exact location of a tissue or a cell is important in the way it develops in to an organ. The arrangement of the cell can't be disturbed in a tissue during the development because the inducer molecules need to be receoved by the cell form the neighbouring cells or tissue.