Complex sentence: Upon UV-B irradiation, light is absorbed by one or more Trp residues-placed adjacent of salt bridging Arg residues which in turn induces the disruption of the salt-bridges at the dimer interface and thus, leads to the molecule's monomerization.
Split into simpler sentences: Upon UV-B irradiation, light is absorbed by one or more Trp residues which are situated adjacent to Arg residues which in form salt bridges across the dimer interfacer. It is thought that this light absorbption induces the disruption of the salt-bridges and thus leads to the molecule's monomerization.