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Hox genes encoding homeodomain-containing transcription factors control the embryogenesis and the specification ofvarious tissue structures during animal development.The specific regional functions of individual Hox genes largely reflect theirrestricted expression patterns,the disruption of which can lead to developmental defects and disease.In silkworm,there are morethan 30 mutants (E group) exhibiting multiple phenotypes,such as extra color markings,supernumerary or defective legs,abnormalsilkgland,defective wings and embryonic lethality.Here,we identified the mutation region responsible for the E mutants bypositional clone.The results showed that they are related to the defect of Hox gene cluster,mainly caused by mutation of the Antp,Ubx,abd-A and Abd-B.The mutations are located both in the gene coding region,which destroy the encoding protein,and in theintergenic region,which affect Hox gene expression patterns.The long non-coding RNAs (lncRNAs) and miRNAs were also beenidentified in the intergenic region between hox genes,which supposed to implicate in the control of Hox gene expression.Byanalyzed the role of Hox genes in the tissues differentiation in silkworm,some new findings got in the silkworm were opposed toprevious reports in Drosophila and other insects.For instance,the Antp gene was found to control the wing development in silkworm,while the Antp gene is not affect the wings identity in Drosophila and Tribolium castaneum.In silkworm,the Abd-A gene promotesthe proleg development.Ectopic expressed Abd-A gene in the A2 segment actives the ectopic dll expression and thereby inducesextral prolegs.However,the Abd-A gene inhibits the leg development by repressing dll expression in Drosophila.The research onHox genes and their roles in establishing the body structures in silkworm will improve our understanding the regulatory mechanismsof Hox gene during vertebrate development.