Different sensitivities of avian- and mammalian-haemoglobin synthesis to elevated temperatures

Avian- and mammalian-haemoglobin synthesis show different sensitivities to elevated temperatures. Temperature-dependent, reversible polyribosome disaggregation in avian cells occurs only at 45 degrees C, which is 3 degrees higher than the temperature for mammalian cells, and seems to be due to a block in the initiation of new polypeptide chains. The implications of these findings are discussed.