Big Spider, Big Genome: Chromosome-level genome of a North American tarantula (Aphonopelma marxi) and comparative genomics across 300 million years of spider evolution

  Image Credit: WikiCommons Big Spider, Big Genome: Chromosome-level genome of a North American tarantula (Aphonopelma marxi) and comparative genomics across 300 million years of spider evolution Abstract The comparison of chromosome-level genomes allows biologists to investigate new axes of organismal evolution. Spiders comprise a significant proportion of known arachnid diversity, with many complex morphologies and unique natural histories, yet comparative genomics in spiders has been limited due to the number of available genomes. We present a de novo chromosomal reference genome of a mature male tarantula, Aphonopelma marxi, and comparatively examine spider genome evolution across the Order Araneae. Using PacBio HiFi and Hi-C sequencing, the final 6.5 Gb assembly consists of 17 autosomes, 1 X chromosome, and 127 unplaced scaffolds, with an N50 of 370 Mb and Arachnida (odb10; 2934 genes) BUSCO of 96.7%. By comparing 20 additional spider genomes from 15 families, we find mygalomo...

Bioactivity profiling of spider venoms reveals predominant hyaluronidase activities

 

Bioactivity profiling of spider venoms reveals predominant hyaluronidase activities

Abstract

Spider venoms are primarily composed of small neurotoxic peptides. However, recent studies suggested a hitherto overlooked diversity of spider venom enzymes, although their functional space still remains largely unexplored. We tested 10 spider venoms for enzymatic activities covering six enzyme classes and found that all tested enzymatic activities can be detected in at least some of the venoms and that hyaluronidases exhibit particularly high enzymatic activities. With this, our study provides functional evidence for the proposed biological significance of enzymes in spider venoms, but more detailed investigations are required.
Dresler, J., Herzig, V., Schulte, L., & Lüddecke, T. (2025). Bioactivity profiling of spider venoms reveals predominant hyaluronidase activities. Toxicon, 108667. https://doi.org/10.1016/j.toxicon.2025.108667