NTGLO - A TOBACCO HOMOLOG OF THE GLOBOSA FLORAL HOMEOTIC GENE OF ANTIRRHINUM-MAJUS - CDNA SEQUENCE AND EXPRESSION PATTERN

We report the cloning and DNA sequence of a cDNA from Nicotiana tabacum, NTGLO, as well as the pattern of expression of the NTGLO gene in wild-type tobacco plants. The NTGLO cDNA encodes a protein of 209 amino acids, which shows 73% identity with the GLO protein encoded by the GLO gene of Antirrhinum majus, a homeotic gene involved in the genetic control of flower development. Northern blot analysis shows that the NTGLO gene is expressed mainly in floral organs and, within the flower, expression is restricted to petals and stamens. The NTGLO gene most probably represents a true homologue of the GLO gene because: i) the MADS boxes, of the two genes are highly homologous (56 out of 58 amino acids are identical): ii) at the carboxy-terminal a block of 19 amino acids is perfectly conserved between the NTGLO and GLO proteins and iii) their expression patterns in floral organs are identical.