Identification and molecular analysis of a multigene family encoding calliphorin, the major larval serum protein of Calliphora vicina

Abstract

A library of Calliphora vicina genomic DNA was constructed in the λEMBL3 vector and screened for recombinant phages containing chromosomal segments encoding calliphorin, the major larval serum protein (LSP) of Calliphora. A large series of recombinants hybridizing with in vitro labelled poly(A)+ RNA from Calliphora larval fat bodies and with specific probes derived from the LSP‐1 genes of Drosophila melanogaster was isolated. Five of these phages, chosen at random, were shown by hybrid selection to retain calliphorin mRNA specifically. Eleven calliphorin mRNA‐homologous regions were located on restriction maps of these phages by hybridization with 5′ end‐labelled poly(A)+ RNA from Calliphora larval fat bodies. Each phage contains at least two calliphorin genes arranged in direct repeat orientation and seperated by 3.5–5 kb intergenic regions. The genes display similar but not identical restriction patterns. Filter hybridization and heteroduplex analysis indicate that they share a detectable homology with the LSP‐1β gene of D. melanogaster. Whole genome Southern analysis showed that these genes belong to a large family of closely related calliphorin genes which were found by in situ hybridization to polytene chromosomes of trichogen cells to be clustered in region 4a of chromosome 2 of Calliphora vicina.

Life‐history plasticity after attaining a dietary threshold for reproduction is associated with protein storage in flesh flies

“…These arylphorin/LSP-1 reserves were depleted during the first week of adulthood in all treatment groups, including those not fed protein as adults. Our observation that arylphorin/LSP-1 levels decline from eclosion through adulthood are consistent with observations in the other higher flies, D. melanogaster, C. vicina and M. domestica, which do not synthesize LSP-1 as adults (Schenkel et al 1985;Benes et al 1990;Capurro et al 2000).…”

“…1991). Similarly, the flesh‐eating fly C. vicina contains more than ten copies of the arylphorin/LSP‐1 gene, none of which show apparent functional differentiation (Schenkel et al . 1985).…”

“…While each of these three proteins in D. melanogaster can be distinguished in non-denaturing-PAGE electrophoresis, there are no apparent functional differences between the three proteins and they can combine with each other to produce the larger functional hexamerins (Roberts et al 1991). Similarly, the flesh-eating fly C. vicina contains more than ten copies of the arylphorin/LSP-1 gene, none of which show apparent functional differentiation (Schenkel et al 1985). Our detection of the S. crassipalpis LSP-2 homologue as a single band was also expected because both D. melanogaster and C. vicina contain only one LSP-2 gene and one electrophoretic form of the protein (Benes et al 1990;Burmester et al 1998).…”

Expression patterns of the larval and adult hexamerin genes of Musca domestica

“…A gene amplification protocol (5′ rapid amplification of cDNA ends ( race )) was used to generate a second clone, A2, which contained a portion of the 5′ end of the transcription product. The deduced amino acid sequences of A1 and A2 showed 71% identity with calliphorin, a previously characterized Calliphora vicina hexamerin ( Schenkel et al. , 1985) (Table 1).…”

The Evolution of Hexamerins and the Phylogeny of Insects

“…Although LSP-1 of D. melanogaster and arylphorin of C. vicina are coded by multigene families, the distribution of their members is different: while the Acalyptrata, like the Drosophilidae (Akam et al 1978;Brock and Roberts 1983) and Ceratitis capitata (Chrysanthis et al 1994), possess two or three Lsp-1-like genes scattered in the genome, in the Calyptratae, e.g., C. vicina (Schenkel et al 1985), Lucilia cuprina (Thomson et al, 1976), and S. peregrina (Tahara et al, 1984), several Lsp-1/ arylphorin-like genes are clustered as a multigene family at a single site in the genome. Figure 3 shows that the arylphorin genes of C. vicina and S. peregrina probably evolved from the same ancestor like Lsp-1␣ and Lsp-1␤ of D. melanogaster but that LSP-1␥ represents another branch of these hexamerins which was lost in the Calyptratae.…”