sentence: Many non RD LRR-RLKs such as LRK10 , FLS2 ( G ó mez-G ó mez and Boller , 2002 ; G ö hre et al ., 2008 ) , and Xa21 ( da Silva et al ., 2004 ) do not autophosphorylate the activation loop and act as potential pathogen / microbe-associated molecular pattern recognition receptors ( Dardick and Ronald , 2006 ) .