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1. Molecular phylogeny of Spirotrichonymphea (Parabasalia) with emphasis on Spironympha , Spirotrichonympha , and three new genera Pseudospironympha , Nanospironympha , and Brugerollina

   https://doi.org/10.1111/jeu.12967  

   Noda, Satoko; Kitade, Osamu; Jasso‐Selles, Daniel E.; Taerum, Stephen J.; Takayanagi, Miki; Radek, Renate; Lo, Nathan; Ohkuma, Moriya; Gile, Gillian H. (February 2023, Journal of Eukaryotic Microbiology)

   Abstract Spirotrichonymphea, one of the six classes of phylum Parabasalia, are characterized by bearing many flagella in spiral rows, and they occur exclusively in the guts of termites. Phylogenetic relationships among the 13 described genera are not well understood due to complex morphological evolution and a paucity of molecular data. One such understudied genus isSpironympha. It has been variously considered a valid genus, a subgenus ofSpirotrichonympha, or an “immature” life cycle stage ofSpirotrichonympha. To clarify this, we sequenced the small subunit rRNA gene sequences ofSpironymphaandSpirotrichonymphacells isolated from the hindguts ofReticulitermesspecies andHodotermopsis sjostedtiand confirmed the molecular identity ofH. sjostedtisymbionts using fluorescence in situ hybridization.Spironymphaas currently circumscribed is polyphyletic, with bothH. sjostedtisymbiont species branching separately from the “true”SpironymphafromReticulitermes. Similarly, theSpirotrichonymphasymbiont ofH. sjostedtibranches separately from the “true”Spirotrichonymphafound inReticulitermes. Our data supportSpironymphafromReticulitermesas a valid genus most closely related toSpirotrichonympha, though its monophyly and interspecific relationships are not resolved in our molecular phylogenetic analysis. We propose three new genera to accommodate theH. sjostedtisymbionts and two new species ofSpirotrichonymphafromReticulitermes. 

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2. Preparation and Characterization of N , N′ ‐Dialkyl‐1,3‐propanedialdiminium Chlorides, N , N′ ‐Dialkyl‐1,3‐propanedialdimines, and Lithium N , N′ ‐Dialkyl‐1,3‐propanedialdiminates

   https://doi.org/10.1002/hlca.202200152  

   Schmit, Claire E.; Girolami, Gregory S. (May 2023, Helvetica Chimica Acta)

   Abstract We describe convenient preparations ofN,N′‐dialkyl‐1,3‐propanedialdiminium chlorides,N,N′‐dialkyl‐1,3‐propanedialdimines, and lithiumN,N′‐dialkyl‐1,3‐propanedialdiminates in which the alkyl groups are methyl, ethyl, isopropyl, ortert‐butyl. For the dialdiminium salts, the N₂C₃backbone is always in thetrans‐s‐transconfiguration. Three isomers are present in solution except for thetert‐butyl compound, for which only two isomers are present; increasing the steric bulk of theN‐alkyl substituents shifts the equilibrium away from the (Z,Z) isomer in favor of the (E,Z), and (E,E) isomers. For the neutral dialdimines, crystal structures show that the methyl and isopropyl compounds adopt the (E,Z) form, whereas thetert‐butyl compound is in the (E,E) form. In aprotic solvents all four dialdimines (as well as the lithium dialdiminate salts) adoptcis‐s‐cisconformations in which there presumably is either an intramolecular hydrogen bond (or a lithium cation) between the two nitrogen atoms. 

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3. The long and short of the S ‐locus in Turnera (Passifloraceae)

   https://doi.org/10.1111/nph.15970  

   Shore, Joel S.; Hamam, Hasan J.; Chafe, Paul D. J.; Labonne, Jonathan D. J.; Henning, Paige M.; McCubbin, Andrew G. (July 2019, New Phytologist)

   Summary Distyly is an intriguing floral adaptation that increases pollen transfer precision and restricts inbreeding. It has been a model system in evolutionary biology since Darwin. Although theS‐locus determines the long‐ and short‐styled morphs, the genes were unknown inTurnera. We have now identified these genes.We used deletion mapping to identify, and then sequence,BACclones and genome scaffolds to constructS/shaplotypes. We investigated candidate gene expression, hemizygosity, and used mutants, to explore gene function.Thes‐haplotype possessed 21 genes collinear with a region of chromosome 7 of grape. TheS‐haplotype possessed three additional genes and two inversions.TsSPH1was expressed in filaments and anthers,TsYUC6in anthers andTsBAHDin pistils. Long‐homostyle mutants did not possessTsBAHDand a short‐homostyle mutant did not expressTsSPH1.Three hemizygous genes appear to determine S‐morph characteristics inT. subulata. Hemizygosity is common to all distylous species investigated, yet the genes differ. The pistil candidate gene,TsBAHD, differs from that ofPrimula, but both may inactivate brassinosteroids causing short styles.TsYUC6is involved in auxin synthesis and likely determines pollen characteristics.TsSPH1is likely involved in filament elongation. We propose an incompatibility mechanism involvingTsYUC6andTsBAHD. 

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4. Tradeoffs between bite force and gape in Eulemur and Varecia

   https://doi.org/10.1002/jmor.21699  

   Laird, Myra F; Polvadore, Taylor A; Hirschkorn, Gabrielle A; McKinney, Julie C; Ross, Callum F; Taylor, Andrea B; Terhune, Claire E; Iriarte‐Diaz, Jose (May 2024, Journal of Morphology)

   Abstract In 1974, Sue Herring described the relationship between two important performance variables in the feeding system, bite force and gape. These variables are inversely related, such that, without specific muscular adaptations, most animals cannot produce high bite forces at large gapes for a given sized muscle. Despite the importance of these variables for feeding biomechanics and functional ecology, the paucity of in vivo bite force data in primates has led to bite forces largely being estimated through ex vivo methods. Here, we quantify and compare in vivo bite forces and gapes with output from simulated musculoskeletal models in two craniofacially distinct strepsirrhines:Eulemur, which has a shorter jaw and slower chewing cycle durations relative to jaw length and body mass compared toVarecia. Bite forces were collected across a range of linear gapes from 16 adult lemurs (suborder Strepsirrhini) at the Duke Lemur Center in Durham, North Carolina representing three species:Eulemur flavifrons(n = 6; 3F, 3M),Varecia variegata(n = 5; 3F, 2M), andVarecia rubra(n = 5; 5F). Maximum linear and angular gapes were significantly higher forVareciacompared toEulemur(p = .01) but there were no significant differences in recorded maximum in vivo bite forces (p = .88). Simulated muscle models using architectural data for these taxa suggest this approach is an accurate method of estimating bite force‐gape tradeoffs in addition to variables such as fiber length, fiber operating range, and gapes associated with maximum force. Our in vivo and modeling data suggestVareciahas reduced bite force capacities in favor of absolutely wider gapes compared toEulemurin relation to their longer jaws. Importantly, our comparisons validate the simulated muscle approach for estimating bite force as a function of gape in extant and fossil primates. 

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5. The period gene alters daily and seasonal timing in Ostrinia nubilalis

   https://doi.org/10.1101/2024.11.02.621642  

   Dayton, Jacob N; Dopman, Erik B (November 2024, bioRxiv)

   Summary The timing of insects’ daily (feeding, movement) and seasonal (diapause, migration) rhythms affects their population dynamics and distribution. Yet, despite their implications for insect conservation and pest management, the genetic mechanisms underlying variation in timing are poorly understood. Prior research in the European corn borer moth (Ostrinia nubilalis) associated ecotype differences in seasonal diapause and daily activity with genetic variation at the circadian clock geneperiod(per). Here, we demonstrate that populations with divergent allele frequencies atperexhibit differences in daily behavior, seasonal development, and the expression of circadian clock genes. Specifically, later daily activity and shortened diapause were associated with a reduction and delay in the abundance of cyclingpermRNA. CRISPR/Cas9-mediated mutagenesis revealed thatperand/or an intact circadian clock network were essential for the appropriate timing of daily behavior and seasonal responsiveness. Furthermore, a reduction ofpergene dosage inperheterozygous mutants (per^-/+) pleiotropically decreased the diapause incidence, shortened post-diapause development, and delayed the timing of daily behavior, in a manner phenotypically reminiscent of wild-type individuals. Altogether, this combination of observational and experimental research strongly suggests thatperis a master regulator of biological rhythms and may contribute to the observed life cycle differences between bivoltine (two generation) and univoltine (one generation)O. nubilalis. HighlightsNatural ecotypes with divergentperiod(per) genotypes differ in their daily and seasonal responses to photoperiodLater daily activity, reduced diapause incidence, and shorter post-diapause development is associated with reducedpermRNA abundanceperis essential for short-day recognition and daily timingReducedpergene dosage shortened post-diapause development and delayed locomotor activity 

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