Genomic lambda-Dash library constructed from Lupinus albus nuclear DNA was screened using a fragment of the beta-tubulin cDNA (beta 8-31) clone of Chlamydomonas reinhardtii as probe. One of the positive recombinant phages was isolated, subcloned and analysed by sequencing. We present here nucleotide and derived amino acid sequences of the beta-tubulin gene, designated as L beta 1 and identified by similarity with other beta-tubulins. The L beta 1-encoded protein reveals a very high degree of similarity with other plant tubulins and contains consensus sequences for binding guanine base, phosphate and Mg2+. Northern analysis of total RNA isolated from roots, leaves, flowers and pools revealed that Lupinus albus beta-tubulin genes are constitutively expressed in all studied plant tissues.