Fig 1.
Ca2+ channels in pollen tubes and pistils in Arabidopsis and rice.
The Ca2+ gradient in pollen tubes is created by members of the CNGC and GLR families (left). Xu et al. [2] reveal a role of OsCNGC13 in the TT of the rice style, where a CNGC-mediated Ca2+ signal is required to induce cell death, which is necessary for the pollen tube to grow through the TT to reach the ovary (right). A role for CNGCs in PCD formation had been previously shown for AtCNGC11/12 [21]. CNGC, cyclic nucleotide-gated channel; GLR, glutamate receptor-like; PCD, programmed cell death; TT, transmission tract.