Cicileus derradji sp. nov., a new species from southern Algeria (Scorpiones: Buthidae)

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  Cicileus derradji sp. nov., a new species from southern Algeria (Scorpiones: Buthidae) Abstract A new scorpion species, Cicileus derradji sp. nov., is described from Tin Zaouatine District, In Guezzam Province, southern Algeria. The description is based on an adult male holotype, an adult female paratype and a juvenile specimen, and is supported by detailed morphological analyses, including colouration, morphometrics, carination patterns and trichobothrial arrangement. This discovery extends the known distribution of the genus Cicileus approximately 500 km southwestward within Algeria. With the addition of this species, the number of recognised species in the genus increases to six. The new species is compared with all previously known species of Cicileus , and detailed colour photographs, including images taken under ultraviolet illumination, are provided. Derradj, L., Aydın Yağmur, E., Benali, N., & Bikada, M. (2026). Cicileus derradji sp. nov., a new species from south...

GLP-1 receptor agonist properties of a chimeric peptide derived by hybridization of Latrodectus αLatrotoxin and Heloderma Exendin-4

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GLP-1 receptor agonist properties of a chimeric peptide derived by hybridization of Latrodectus αLatrotoxin and Heloderma Exendin-4

Abstract

Chimeric peptides comprised of amino acid sequence motifs found within hormones, neuropeptides, and insect or lizard toxins are now under investigation for their potential use in therapeutics. Here, we report the discovery of one such peptide designated as Black Widow Spider-Exendin-4 (BW-Ex-4). It consists of a putative G protein-coupled receptor (GPCR) binding domain present within αLatrotoxin (αLTX) isolated from Latrodectus, and fused to N- and C- terminal motifs found within the glucagon-like peptide-1 receptor (GLP-1R) agonist Exendin-4 isolated from Heloderma. FRET reporter assays that monitor cAMP production establish BW-Ex-4 to be a specific GLP-1R agonist without any stimulatory action at glucose-dependent insulinotropic peptide (GIP), glucagon, or corticotropin releasing hormone (CRH) receptors. Structural modeling studies of the predicted BW-Ex-4 binding sites at GPCRs of Family B provide new insights concerning the molecular basis for chimeric peptide stimulatory actions at the GLP-1R. We also report that BW-Ex-4 acts in obese hyperglycemic Leprdb/db mice to suppress appetite, lower body weight, improve glucoregulation, and to reduce circulating levels of pro-inflammatory cytokines. Collectively, these findings establish combinatorial chimeric peptide chemistry in which αLTX serves as a molecular scaffold for the design of hybrid peptides with novel GPCR stimulating properties.
Chepurny, O. G., Liles, A. N., Cham, N., Matsoukas, M., Liapakis, G., Meng, Q., Cooney, R. N., Doyle, R. P., & Holz, G. G. (2025). GLP-1 receptor agonist properties of a chimeric peptide derived by hybridization of Latrodectus αLatrotoxin and Heloderma Exendin-4. General and Comparative Endocrinology, 114745. https://doi.org/10.1016/j.ygcen.2025.114745