Extended Data Fig. 6: Desensitization of hypo-osmosensitive OSCA2.1 and OSCA2.2 Ca2+ channels expressed in HEK293 cells.
From: Osmosensor-mediated control of Ca2+ spiking in pollen germination
a, Representative plots show HOSCA desensitization of OSCA2.1, OSCA2.2, and TRPV4 when expressed in HEK293 cells with pcDNA3.2 as a control. HEK293 cells were treated with the isosmotic solution (300 mOsm; black) and hypo-osmotic solution (140 mOsm; gray) repetitively three times, and [Ca2+]i were analyzed by Fura-2 emission ratios. Data are mean ± s.d. (n = 3 independent experiments). Similar results were seen in > 10 times. b, Quantification of HOSCA desensitization from experiments similar to a. OSCA2.1 and OSCA2.2 showed over 50% of desensitization, while TRPV4 showed only about 10–20% of desensitization. The cells expressing pcDNA3.2 almost did not show any desensitization. The properties of HOSCA kinetics and desensitization for OSCA2.1 and OSCA2.2 expressed in HEK293 cells were consistent with the HOSCA kinetics in planta as shown in Fig. 3a,b. The 1st HOSIC was arbitrarily set to 1, and data are mean ± s.d. (n = 3 or 4 independent experiments). Similar results were seen in > 10 times.
