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...

Latrodectus spp. toxins outside venom glands: past, present and future

 

Latrodectus spp. toxins outside venom glands: past, present and future

ABSTRACT

Latrodectus spp. are one of the highly poisonous spiders known in the world. Interestingly, the spiders not only produce and secrete toxins by their venom glands, but also have toxic components in other parts of the adult spiders, and even in the newborn spiderlings and unhatched eggs. The venom and venom toxins secreted by their venom glands have been quite extensively studied and, comparatively, the study on the toxins outside venom glands is limited. Although the toxins outside venom glands were discovered at a very early time, it is not until recently that the molecular basis and mechanism of the toxicity outside venom glands have been relatively systematically investigated, which have significantly expanded our understanding of the spider toxins. This review summarizes the progresses in the research on the Latrodectus spp. particularly black widow spider toxins outside venom glands, with an emphasis on the toxins from the spider eggs.
Wang, X. (2025). Latrodectus spp. Toxins outside venom glands: Past, present and future. Toxicon, 108437. https://doi.org/10.1016/j.toxicon.2025.108437