The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant–water relations in the commercial strawberry(Fragaria x ananassa).Aquaporins are water channel proteins ...The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant–water relations in the commercial strawberry(Fragaria x ananassa).Aquaporins are water channel proteins that allow water to cross(intra)cellular membranes.In Fragaria x ananassa,few of them have been identified hitherto,hampering the exploration of the water transport regulation at cellular level.Here,we present new aquaporin coding sequences belonging to different subclasses:plasma membrane intrinsic proteins subtype 1 and subtype 2(PIP1 and PIP2)and tonoplast intrinsic proteins(TIP).The classification is based on phylogenetic analysis and is confirmed by the presence of conserved residues.Substrate-specific signature sequences(SSSSs)and specificity-determining positions(SDPs)predict the substrate specificity of each new aquaporin.Expression profiling in leaves,petioles and developing fruits reveals distinct patterns,even within the same(sub)class.Expression profiles range from leaf-specific expression over constitutive expression to fruit-specific expression.Both upregulation and downregulation during fruit ripening occur.Substrate specificity and expression profiles suggest that functional specialization exists among aquaporins belonging to a different but also to the same(sub)class.展开更多
文摘The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant–water relations in the commercial strawberry(Fragaria x ananassa).Aquaporins are water channel proteins that allow water to cross(intra)cellular membranes.In Fragaria x ananassa,few of them have been identified hitherto,hampering the exploration of the water transport regulation at cellular level.Here,we present new aquaporin coding sequences belonging to different subclasses:plasma membrane intrinsic proteins subtype 1 and subtype 2(PIP1 and PIP2)and tonoplast intrinsic proteins(TIP).The classification is based on phylogenetic analysis and is confirmed by the presence of conserved residues.Substrate-specific signature sequences(SSSSs)and specificity-determining positions(SDPs)predict the substrate specificity of each new aquaporin.Expression profiling in leaves,petioles and developing fruits reveals distinct patterns,even within the same(sub)class.Expression profiles range from leaf-specific expression over constitutive expression to fruit-specific expression.Both upregulation and downregulation during fruit ripening occur.Substrate specificity and expression profiles suggest that functional specialization exists among aquaporins belonging to a different but also to the same(sub)class.
