Evolutionary assembly of cooperating cell types in an animal chemical defense system

Abstract

Highlights d A rove beetle defense gland reveals how evolution builds new organs d Two secretory cell types work together, one making a solid toxin, the second a solvent d New cellular functions evolved by combining ancient transcriptome modules and pathways d Evolution of each cell type was shaped by adaptive coevolution between the cell types

Solvent Properties Influence the Rheology and Pinching Dynamics of Polyelectrolyte Solutions: Thickening the Pot with Glycerol and Cellulose Gum

“…Additional details about the experimental setup and design considerations, specific advantages of DoS rheometry contrasted to other extensional rheology methods, and the various approaches to analyzing radius evolution datasets are included in our previous contributions. ,,,− ,− We investigate and describe the extensional rheological response of complex fluids such as neutral and charged polymer solutions, inks, nail lacquers, surfactant-based cosmetics (shampoos and conditioners), proteins such as egg albumin, spinnable polymer solutions, , and foods (honey, molasses, mayo, and ketchup). ,,,− ,− Since we introduced DoS rheometry in 2015, it has emerged as the method of choice for innumerable studies benefitting from the virtues of a simplified, cost-efficient setup and the ability to analyze the pinching dynamics and extensional rheological response of complex fluids, including those with viscosity comparable to water or weak elasticity, even with sub-millisecond relaxation times. − …”

Evolution of homology: From archetype towards a holistic concept of cell type

“…Genetic heterogeneity inherently marks novel cell types, as can be illustrated, for instance, with a report on sea urchin's larval pigment cells: those are traditionally considered a morphological and functional novelty of echinoid echinoderms and also form a distinct cluster in the urchin's single‐cell atlas, while they turn to comprise a ‘hybrid’ of immune mesenchyme and neuronal‐type GRNs in comparison with a sea star (Meyer et al, 2022). The salient examples of cell type novelty emerging via assembly of different labour‐executing components can be observed among the exceptional diversity of exocrine glands in insects (Brückner et al, 2021; Kishi & Parker, 2021).…”

“…The following references are intended to acquaint the interested reader with the recent single‐cell evidence on animal cell diversity in both model and nonmodel species, which would not be appropriate to detail in a single review but is still citable in terms of the number of publications. The wealth of scRNA‐Seq data already generated is expected to grow rapidly and already covers major animal lineages: Porifera (Musser et al, 2021; Sebé‐Pedrós, Chomsky, et al, 2018), Ctenophora and Placozoa (Sebé‐Pedrós, Chomsky, et al, 2018), Cnidaria (Chari et al, 2021; Hu et al, 2020; Levy et al, 2021; Sebé‐Pedrós, Saudemont, et al, 2018; Siebert et al, 2019), Acoela (Duruz et al, 2021; Hulett et al, 2022), Plathelminthes (Fincher et al, 2018; Li et al, 2021; Plass et al, 2018), Annelida (Achim et al, 2018; Shao et al, 2020), Arthropoda (Allen et al, 2020; Brückner et al, 2021; Croset et al, 2018; Davie et al, 2018; Dillon et al, 2022; Hung et al, 2020; Karaiskos et al, 2017; Rust et al, 2020; Slaidina et al, 2020), Nematoda (J. Cao et al, 2017; Packer et al, 2019), Echinodermata (Foster et al, 2020; Massri et al, 2021; Meyer et al, 2022; Paganos et al, 2021), Urochordata (C. Cao et al, 2019; Horie et al, 2018; Sladitschek et al, 2020), as well as the most densely sampled Craniota (Briggs et al, 2018; J. Cao et al 2019, 2020; Farrell et al, 2018; Han et al, 2020; Hodge et al, 2019; Pijuan‐Sala et al, 2019; Regev et al, 2017; Shafer et al, 2022; The Tabula Muris Consortium, 2018; Tosches et al, 2018; D. E. Wagner et al, 2018).…”

Evolution as Explanation: The Origins of Neural Codes and their Efficiencies

“…We emphasize, however, that such redundancy does not mean natural selection does not operate, whatsoever. Indeed, for many macroevolutionary processes, the outcomes of neutral events can be co-opted for more adaptive means, such that they facilitate functional dependencies and neofunctionalizations [35,8,28]. Speculating on possible systems-level functions and goals is still essential for neuroscience.…”

“…For example, both GCA and GCG genetic triplets, or codons, encode for the alanine amino acid, even though the sequences differ by a base pair. The GCA → GCG mutation is synonymous or silent 8. An interesting observation for the invertebrate neuroscientist.…”