Bamboo shoots grow quickly through the rapid elongation of internodes,but the preeise molecular mecha- nisms underlying this process remain unknown.We used a combination of suppressive subtractive hybridization (SSH),dot blotting,sequencing and bioinformatics to identify Phyllostachys pubescens genes that are differentially cxprcssed in rapidly elongating Vs.static internodes (SIs).We isolated 1020 expressed sequence tags (ESTs) by SSH,173 0f which were shown to be differentially expressed by dot blotting.We then sequenced the 20 ESTs showing the greatest difference in expression,13 0f which were prefer- entially expressed in elongating interodes and seven SIs.Functional charaeterization of the ESTs showed that rapid internode elongation requires meristem initiation and prolif- cration,high-level protein synthesis cellular respiration,and cell wall 5ynthesis,as well as the regulation of the activated methyl cycle,gibberellin and brassinosteroid biosynthesis,and their signal transduction pathways.