Plasma Membrane Cyclic Nucleotide Gated Calcium Channels Control Land Plant Thermal Sensing and Acquired Thermotolerance

ABSTRACT: Analysis of transcriptome in moss Physcomitrella patens CNGCb null mutant at 25 and 34 degrees C for 30 minutes. Results provide insight into role of CNGCb in acquired thermotolerance induced by non-lethal heat treatment. Typically at dawn of a hot summer day, land plants need precise molecular thermometers to sense harmless increments in the ambient temperature to timely develop a heat-shock response (HSR) and accumulate protective heat shock proteins (Hsps), in anticipation of upcoming harmful temperatures at mid-day. Here, we found that the CNGCb gene from Physcomitrella patens and its Arabidopsis ortholog CNGC2, encode for a component of cyclic nucleotide gated Ca2+ channels acting as the primary thermosensors of land plant cells. Disruption of CNGCb or CNGC2 produced a hyper-thermosensitive phenotype, giving rise to a HSR and acquired thermotolerance at significantly milder heat-priming treatments than in wild type plants. In an aequorin-expressing moss, CNGCb loss-of-function caused altered Ca2+ signaling and a sustained Ca2+ influx. Patch clamp recordings on moss protoplasts showed the presence of three distinct thermo-responsive Ca2+-channels in wild type cells. Deletion of CNGCb led to a total absence of one, and it increased the open probability of the remaining two thermo-responsive Ca2+ channels. Thus, both in Arabidopsis and moss, CNGC2 and CNGCb are expected to form with other related CNGCs, heteromeric Ca2+ channels in the plasma membrane that respond to mild increments in the ambient temperature by triggering an optimal HSR, leading to the onset of plant acquired thermotolerance. The WT moss tissues were heat-shocked for a half an hour at 34°C and 38°C and CNGCb at 25and 34°C followed by liquid nitrogen freezing. Total RNA was isolated using RNeasy Mini Kit (QIAGEN, Hilden, Germany) and two biological replicate samples for each treatment, were extracted. An Agilent-certified microarray service lab (MOgene, LC, St. Louis, MO, USA) was used to verify the integrity of the RNA and perform the microarray experiments. Two biological replicates were performed.

ORGANISM(S): Physcomitrella patens

SUBMITTER: Andrija Finka 

PROVIDER: E-GEOD-36301 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress