Comparisons obtained when the 2 TMS hairpin segments from Orai homologues were compared with 2 TMS segments of CDF carriers. (A) The maximal comparison score value was obtained when segment 3-4 of CDF was compared with segment 1-2 of Orai (14.6 S.D.). (B) When segment 5-6 of a CDF homologue was compared with segment 3-4 of an Orai homologue, the second largest score (8.6 S.D.) was obtained. Significant similarity was not found when TMSs 1-2 of CDF proteins were compared with CRAC Orai homologues (Table 1B), leading to the proposal set forth in Figure 5.