Haemoglobin expression in germinating barley

Polyclonal antibodies to purified recombinant barley haemoglobin (Hb) have been raised in rabbits and used to investigate its expression in monocotyle donous plants. Very little or no Hb expression was observed in dry barley s eeds but germination resulted in the expression of Hb which peaked at 2-3 d ays after imbibition. Hb expression was also observed in maize, wheat, wild oat and Echinochloa crus-galli seeds during germination. Dissection of tis sues from the barley seedlings showed that most of the haemoglobin was expr essed in the root and seed coat (aleurone layer), with very little in the c oleoptile. Imbibition of half-seeds or excised embryos resulted in the expr ession of haemoglobin. ATP measurements of barley embryos showed that ATP l evels quickly increase after imbibition. alpha-Amylase activity was also de termined in embryos to correlate Hb expression with a well-characterized ge rmination response. The results demonstrate that Hb expression is a normal consequence of germination.