1. excellent cell biology hormone and light signaling pathways operative few cell types & simple developmental pattern polar tip growth and division tolerant to water stress -------------------------------- A Model System for Functional Studies draft genome assembled* gene targeting & RNAi gene id from 2-d gels 4x44 Agilent microarray gene id by genetic map position insertion and deletion libraries Quatrano, R. S., et al. (2007). Current Opinion in Plant Biology 10: 182-189. *Rensing, et al. (2008). Science 319: 64-69. Physcomitrella patens Haploid, single-cell layer, leaf-like gametophores of P. patens