Abstract
It is known that vessel and fiber cells form thick secondary cell walls (SCWs). TED6/7 genes, encoding membrane proteins, have been isolated as genes strongly expressed during xylem vessel cells differentiation. Suppression of expression of both TED6/7 genes induced aberrant SCW formation, and TED6 protein formed protein complexes with a subunit of the SCW-related cellulose synthase. These data suggested that TED6/7 play important roles in SCW formation.
To elucidate the role of TED6/7, here we attempt to purify and identify protein complexes which bind to TED6 protein. We constructed vectors for the expression of TED6 protein fused with the tag sequence driven by TED6 promoter (TED6pro:TED6-tag), which were introduced into a transgenic plant overexpressing VND7, a key regulator of xylem vessel differentiation, under the control of the DEX induction system. We extracted crude protein and purified protein complexes by antibodies against the tag sequences. By using mass spectrometry, we identified a number of the candidate proteins that form complexes with TED6 protein. We are currently investigating the binding between TED6 and the identified proteins in vivo by BiFC analysis.
