Dual perinatal and developmental expression of the small heat shock proteins [FC12]aB-crystallin and Hsp27 in different tissues of the developing piglet.

Expression of the two closely related heat shock proteins (HSPs), alpha B-crystallin and Hsp27, was studied in various tissues of the developing pig. Expression of alpha B-crystallin was maximum in the lens while expression of Hsp27 was absent. In non-lenticular tissues, both proteins were strongly expressed in heart and muscle. Increases in alpha B-crystallin expression were observed in brain, liver and kidney while Hsp27 was increased in kidney at later stages. Relatively constant expression was found in heart while a decrease in both stress proteins was observed between 28 days and 6 months in skeletal muscle. In the different parts of the gastrointestinal tract, increased expression of alpha B-crystallin was seen following birth and weaning while increased expression of Hsp27 was restricted to weaning. These results are discussed in terms of the protective effects of HSPs during stressful events in the different tissues of the developing pig.