Mamestra configurata serpin-1 homologues: cloning, localization and developmental regulation

Differential expansion and evolution of the exon family encoding the Serpin-1 reactive centre loop has resulted in divergent serpin repertoires among the Lepidoptera

“…Membranes containing the entire BAC library were probed with a cDNA fragment corresponding to a portion of the Serpin-1a gene (Chamankhah et al, 2003) labelled with [α-32 P] dCTP using the Random Primers DNA Labelling System (Invitrogen). Hybridizations were conducted in 0.5 M NaHPO 4 buffer (pH 7.2) and 7% SDS at 65°C overnight.…”

“…While this phenomenon appears to be commonplace among invertebrates (Kruger et al, 2002;Brandt et al, 2004;Bruning et al, 2007) and the biochemical specificities of many of the M. sexta Serpin-1 variants have been characterized, their respective biological functions remain largely unknown (Jiang and Kanost, 1997). The expression of the Serpin-1 gene has been studied in two lepidopterans, M. sexta (Kanost et al,1995) and the bertha armyworm, Mamestra configurata (Chamankhah et al, 2003). In M. configurata, transcript levels peaked in mid-stadium larvae and were highest in the larval fat body and hemocytes.…”

“…Expression declined dramatically at the onset of the molt, likely in response to increasing ecdysone levels, concomitant with the appearance of several hemolymph protease activities. Immunolocalization studies (Chamankhah et al, 2003;Molnar et al, 2001) demonstrated that serpin is associated with hemocytes; however, the bulk is secreted from the fat body into the hemocoel with some being re-localized to the sub-cuticular epidermal region. Two-dimensional electrophoresis coupled with western blot analysis of M. configurata hemolymph revealed 9-10 intact serpin species and additional higher and lower molecular weight forms.…”

“…The characteristics of its regulation and protein localization pattern strongly suggest that the various Serpin-1 gene products play a role in something other than the defense response. Of the three M. configurata Serpin-1 variants previously reported, only one possessed a RCL that bore any similarity to a M. sexta serpin variant (Chamankhah et al, 2003). Therefore, to gain insight into the function and evolution of the Serpin-1 gene among Lepidoptera we sequenced the entire M. configurata gene and examined the expression patterns of its nine RCL variants.…”

Isolation, characterization, and recombinant expression of multiple serpins from the cat flea, Ctenocephalides felis

“…Mammalian serpins have been shown to inhibit enzymes involved in coagulation, fibrinolysis, inflammation, fertilization, development, and neuro-muscular patterning. Serpins also have been found in the hemolymph of various invertebrates, including arthropods within the classes Insecta and Crustacea (Miura et al, 1995;Polanowski et al, 1992;Gan et al, 2001;Chamankhah et al, 2003). In insects, serpins have been hypothesized to play a functional role in the inhibition and regulation of serine proteases involved in such critical processes as immunity, development, and wound response (Kanost, 1990(Kanost, , 1999Park et al, 2000;Danielli et al, 2003).…”