The present invention relates to isolation and characterization of novel nucleotide sequences from rice tungro bacilliform virus (RTBV) showing promoter activity in plants. The present invention further relates to the analysis of the functional domains of RTBV promoters by fusing full-length and deleted versions of the RTBV promoter sequences with the bacterial reporter gene GUS. The invention also relates to the study of the expression of the reporter gene in various tissues of transgenic rice and tobacco plants during different stages of development. The present invention also describes an RTBV promoter and its deletions which function in a constitutive or tissue-specific manner to drive the expression of the heterologous nucleic acid sequences in both monocot and dicot plants, cells and tissues.