Thus we propose that BmCaspase N belongs to the effector caspase KPT-330 mechanism subfamily. Bcl 2 family members in silkworms Bcl 2 family members participate at a crucial point in apoptotic pathways. All members share at least one Inhibitors,Modulators,Libraries of four BH domains. Tambunan and colleagues identified BmP109 from samples obtained during silk gland histolysis, a stage of Bombyx mori metamorphosis. However, the function of BmP109 with all four conserved BH regions has not been con firmed in Bombyx mori. We analyzed and cloned the other Bcl 2 family homo log BmBuffy, whose structure is more similar to Buffy of Apis mellifera and bcl 2 of Pediculus humanus corporis. BmBuffy lacks the BH4 domain. The com pleted BmBuffy cDNA is 1632 bp, coding for 292 aa, and the relative predicted molecular mass is 32. 38 kDa.

The sequence similarity and identity are 51% and 27%, respectively, compared with DmBuffy. BIR domain family members in silkworms The BIR domain is a unique structure originally identified in IAP proteins from baculoviruses. At least one BIR motif is essential for the antiapoptotic activity of IAP family members, Inhibitors,Modulators,Libraries but not all BIR containing proteins are IAPs. We identified four proteins containing BIR domains in Bombyx mori, including two IAPs, one Bruce and one survivin. Huang and colleagues cloned the first IAP family member BmIAP from Bombyx mori BmN cells. BmIAP is a specific inhibitor of mammalian caspase 9, but does not directly inhibit the downstream effector proteases caspase 3 and caspase 7. BmIAP inhibits apop tosis induced by Bax but not Fas in vitro. GSK-3 However, the function of BmIAP in vivo is not yet known.

The other IAP family member BmIAP2 is located on the same chro mosome as BmIAP, is 561 aa long and possesses three BIR domains and one Zn2 finger domain. Compared with DIAP1 and DIAP2, BmIAP1 and BmIAP2 have two and three BIR domains, respectively, also. The BmBruce and survivin proteins Inhibitors,Modulators,Libraries each have one BIR domain, with a sequence consistent with the online BIR sequence, and are 4236 aa and 136 aa long, respectively. Besides their size Inhibitors,Modulators,Libraries difference, BmBruce also has an ubiqui tin proteasome binding motif, which is homologous to Drosophila Bruce protein. RHG family members in Drosophila contain the IAP Binding Motif domain in their N terminal, which binds to and removes the inhibitory activity of IAP as well as their structural and functional homologs Smac Diablo in mammals.

However, RHG family proteins connect many different signaling path ways, thereby having a central role in the regulation of programmed cell death in Drosophila, which is very GSK2656157? dif ferent from other species, especially compared to mam malian Smac Diablo. Another IAP inhibitor, Htra2 Omi in mammals and its homolog protein DmHtra Omi in Drosophila, have a function similar to Smac Diablo. DmHtra2 Omi in Drosophila also has serine protease activity.