theseus1 and other members of the crrlk family are important to cellular elongation. in particular, theseus1 and hercules1 (herk1) have shown to perform similar roles in the process of elongation. arabidopsis thaliana plants with a loss-of-function mutation to only one of these proteins will maintain a similar growth rate to the wild-type plant. however, if both proteins are mutated, the plant displays a greatly inhibited growth rate. though the specific mechanism that causes this is unknown, it can be seen that these proteins are redundant but necessary for regular vegetative growth. additionally, both the1 and herk1 function in coordination with the brassinosteroid pathway with a slight regulatory overlap between the two.