The work by IBE researchers Jesus Lozano and Xavier Belles, published in July issue of PLOS ONE deals with the molecular action of juvenile hormone (JH), the master repressor of insect metamorphosis.
Recent research has shown that the JH receptor is the transcription factor methoprene-tolerant (Met), but this has been demonstrated only in the more derived insect groups Holometabola and Paraneoptera. The work reports that this function is present in the cockroach Blattella germanica, a representative of the more basal group of Polyneoptera. We have also studied the function of Met in the last nymphal instar. Our observations in this stage suggest that Met plays a role in the imaginal molt, and possibly has a stimulatory action upon the transcription of Insulin-like peptides, in the absence of JH. It is the first time that the role of Met is studied in the pre-imaginal stage, when JH is absent.

Reference Article: Lozano J, Belles X (2014) Role of Methoprene-Tolerant (Met) in Adult Morphogenesis and in Adult Ecdysis of Blattella germanica. PLoS ONE 9(7):e103614. doi:10.1371/journal.pone.0103614