TemporaJ and Spatial Pattern of Ammonia - Lyase Genel PromoterExpression of in T an ge icthe Pea Phenylalanine Tobacco

Genes encoding phenyla]anine ammonia-tyase (PAL) form a small multigene family with at least three members in pea. Tissue-specific expression of the promoter of a member of PAL gene family (RSR4Ll) was inyestigated in the transgenic tobacco transformants earrying the different modes of chimeric fusion between the RSItaLl promoter and a bacteria] ll-glucuronidase (GUS) gene. In stems, at least, strict corre]ation was found between steady-state levels of Gus-mRNA and enzyme activity. Significantly high leyel of GUS actiyity was obseryed in roots, particularly in meristematic tissues and the pigmented region of peta]s of transgenic tobacco carrying the trans]ational fusion type B (-1,394 to +140 of RSRtlLl connected to Gus), fol]owed by moderately high level of GUS actiyity carrying the translational fusion type A (-1,394 to +117). GUS expression in tissues of mature leayes, howeyer, was very low in these constructs. Extremely low GUS actiyity was obseryed in the transformants of transcriptional fusion type (-1,394 to +5), whilst no activity was detected carry-