Mostly found in bacteria, riboswitches are sequences generally cis regulatory elements that show two main secondary structures. One of the secondary structure hinders gene expression while the other conformation of the riboswitch allows expression of the gene. This switching process occurs because of the presence of a ligand. The process of interconversion is not well understood till now.
In their current research paper Barsacchi M. et al.(2016) have suggested that a sequence called switching sequence is required to causes the interchange between the two conformations of the riboswitch. The proposed SwisSpot technique used by them can help in identifying such sequence.
Swispot software is available at the following site http://www.iet.unipi.it/a.bechini/swispot/
Barasacchi M et. al.(2016). SwiSpot: modelling riboswitches by spotting out switching sequences. Bioinformatics 32(21)3252-3259.