How might temperature affect gene expression?

Question

This is kind of random but I read that for some animals, like alligators and turtles, the gender of the offspring is affected greatly by the temperature the organism lives in. This could be another argument in the global warming debate.

Anyway, this got me wondering... why are the offspring affected in this way? Are s*x determination genes affected by temperature? Can a gene's expression even be altered by temperature? How does this occur?

Just wondering if anyone has any ideas... I for one am kind of puzzled!

Answer 1

Absolutely! The delicate balance that maintains conditions for life within cells and embryos is very sensitive to temperature. Most genes are regulated by transcription factors (proteins that initiate specific expression of particular genes in response to some developmental pathway or signal)

Suppose the transcription factor that determines maleness is unable to fold to the correct shape above 35 degrees Celsius. Then, in organisms where femaleness is the default developmental program, a female will develop.

Other examples of temperature sensitivity can be found outside of gene expression. In some animals, variegated coat colors are caused by temperature fluctuations that cause enzymes that convert colorless chemicals to pigments to malfunction. The result is colored hair in some spaces and colorless hair in others.