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The genus Hexatoma Latreille, 1809 is a large group of aquatic crane flies, with almost 600 species worldwide. The largest subgenus is Eriocera Macquart, 1838, which includes all nine species known from the Korean Peninsula. Molecular methods were used to associate Hexatoma larvae with their putative adult species from South Korea. Mitochondrial Cytochrome c Oxidase Subunit I (COI) gene fragment sequences (DNA barcodes) of recently collected adults of H. (E.) gifuensis, H. (E.) ilwola, H. (E.) pernigrina, and H. (E.) pianigra were compared with twelve sequences of Hexatoma larvae. The larvae of H. (E.) pernigrina, H. (E.) pianigra, and H. (E.) gifuensis were associated with their putative adults. The larvae of H. (E.) gifuensis and H. (E.) pianigra and the larvae and pupae of H. (E.) pernigrina are described and illustrated. The larvae of two species not associated with any adult are described, and their COI gene fragment sequences (DNA barcodes) are presented. This paper presents the morphological characteristics suitable for distinguishing larval species. A key for the identification of larvae of the genus Hexatoma on the Korean Peninsula has been compiled. H (E.) sachalinensis is recorded from the Korean Peninsula for the first time. Our study is the first contribution to the Hexatoma larvae taxonomy using phylogenetic analysis based on mitochondrial COI fragment (DNA barcode) and one of the first attempts to reveal phylogenetic relationships between Hexatoma species using molecular markers.

Retroviral vectors show long-term gene expression in gene therapy through the integration of transgenes into the human cell genome. Murine leukemia virus (MLV), a well-studied gammaretrovirus, has been often used as a representative retroviral vector. However, frequent integrations of MLV-based vectors into transcriptional start sites (TSSs) could lead to the activation of oncogenes by enhancer effects of the genetic components within the vectors. Therefore, the MLV integration preference for TSSs limits its wider use in clinical applications. To reduce the integration preference of MLV-based vectors, we attempted to perturb the structure of the viral integrase that plays a key role in determining integration sites. For this goal, we inserted histones and leucine zippers, having DNA-binding property, into internal sites of MLV integrase. This integrase engineering yielded multiple mutant vectors that showed significantly different integration patterns compared with that of wildtype vector. Some mutant vectors did not prefer the key regulatory genomic domains of human cells, TSSs. Moreover, a couple of engineered vectors did not integrate into the genomic sites near the TSSs of oncogenes. Overall, this study suggests that structural perturbation of integrase is a simple way to develop safer MLV-based retroviral vectors for use in clinical applications.