Sequence, phylogenetic analysis, and molecular modeling of Lutzomyia longipalpis defensin 1 (LlDef1). (A) The complete genomic sequence of the Lutzomyia longipalpis LlDef1 defensin gene containing 1034 nucleotides (nt) is shown. The 5'UTR region contains 518 nt and the 3'UTR 153 nt (lower case gray letters). In the 5'UTR region, potential binding sites for transcription factors Dorsal, Dfd and Caudal are shown (underlined bold lower case letters). The LlDef1 coding region contains 363 nucleotides with a 63 nt intron (gray lower case italic letters). The amino acid prediction indicates an 87 residues peptide (upper case letters), from which 40 correspond to the mature peptide (bold upper case letters). The first vertical bar limits the signal peptide and the second vertical bar divides the pre and pro-peptide. The 6 cysteines of the pro-peptide with the potential to generate 3 disulfide bonds are underlined and the polyadenylation site is indicated. (B) Neighbour-joining tree based on multi alignment created from defensins predicted amino acid sequences of L. longipalpis [JQ970473], A. aegypti [P81602.2], A. gambiae [AAC18575.1], P. duboscqi [P83404.3], Rhodnius prolixus [AAO74624.1], Glossina morsitans [Q8WTD4.1], Culex quinquefasciatus [AEQ27735.1] and Ixodes scapularis [XP_002401521.1], showing the phylogenetic relationship between L. longipalpis and other insect defensins. (C) Putative tertiary structure of the L. longipalpis defensin showing the characteristic architecture of arthropod defensins with two anti-parallel β-sheets (red) and an α-helix (green).