Compositions and methods for regulating expression of heterologous nucleotide sequences in a plant are provided. Compositions include nucleotide sequences for a Setaria italica (Foxtail Millet) (SI-Ubiquitin) and Sorghum bicolor (SB-Ubiquitin) regulatory regions. Also provided is a method for expressing a heterologous nucleotide sequence in a plant using a promoter sequence disclosed herein.