Identification and Functional Analysis of G Protein-Coupled Receptors in 20-Hydroxyecdysone Signaling From the Helicoverpa armigera Genome

G protein-coupled receptors (GPCRs) are the largest family of membrane receptors in animals and humans, which transmit various signals from the extracellular environment into cells. Studies have reported that several GPCRs transmit the same signal; however, the mechanism is unclear. In the present study, we identified all 122 classical GPCRs from the genome of Helicoverpa armigera, a lepidopteran pest species. Twenty-four GPCRs were identified as upregulated at the metamorphic stage by comparing the transcriptomes of the midgut at the metamorphic and feeding stages. Nine of them were confirmed to be upregulated at the metamorphic stage. RNA interference in larvae revealed the prolactin-releasing peptide receptor (PRRPR), smoothened (SMO), adipokinetic hormone receptor (AKHR), and 5-hydroxytryptamine receptor (HTR) are involved in steroid hormone 20-hydroxyecdysone (20E)-promoted pupation. Frizzled 7 (FZD7) is involved in growth, while tachykinin-like peptides receptor 86C (TKR86C) had no effect on growth and pupation. Via these GPCRs, 20E regulated the expression of different genes, respectively, including Pten (encoding phosphatidylinositol-3,4,5-trisphosphate 3-phosphatase), FoxO (encoding forkhead box O), BrZ7 (encoding broad isoform Z7), Kr-h1 (encoding Krüppel homolog 1), Wnt (encoding Wingless/Integrated) and cMyc, with hormone receptor 3 (HHR3) as their common regulating target. PRRPR was identified as a new 20E cell membrane receptor using a binding assay. These data suggested that 20E, via different GPCRs, regulates different gene expression to integrate growth and development.

Effects of thiourea on the skull of Triturus newts during ontogeny

Background In amphibians, thyroid hormone (TH) has a profound role in cranial development, especially in ossification of the late-appearing bones and remodeling of the skull. In the present study, we explored the influence of TH deficiency on bone ossification and resulting skull shape during the ontogeny of Triturus newt hybrid larvae obtained from interspecific crosses between T. ivanbureschi and T. macedonicus. Methods Larvae were treated with two concentrations of thiourea (an endocrine disruptor that chemically inhibits synthesis of TH) during the midlarval and late larval periods. Morphological differences of the cranium were assessed at the end of the midlarval period (ontogenetic stage 62) and the metamorphic stage after treatment during the late larval period. Results There was no difference in the ossification level and shape of the skull between the experimental groups (control and two treatment concentrations) at stage 62. During the late larval period and metamorphosis, TH deficit had a significant impact on the level of bone ossification and skull shape with no differences between the two treatment concentrations of thiourea. The most pronounced differences in bone development were: the palatopterygoid failed to disintegrate into the palatal and pterygoid portions, retardation was observed in development of the maxilla, nasal and prefrontal bones and larval organization of the vomer was retained in thiourea-treated larvae. Conclusions This implies that deficiency of TH caused retardation in development and arrested metamorphic cranium skeletal reorganization, which resulted in divergent cranial shape compared to the control group. Our results confirmed that skull remodeling and ossification of late-appearing bones is TH–dependent, as in other studied Urodela species. Also, our results indicate that TH plays an important role in the establishment of skull shape during the ontogeny of Triturus newts, especially during the late larval period and metamorphosis, when TH concentrations reach their maximum.

A new geographic record of the endangered Telmatobufo venustus (Amphibia: Calyptocephalellidae) in the Biobío Region, Chile

We document the record of Telmatobufo venustus Phillipi (1899) in the Altos de Malalcura sector, Antuco, Biobío Region, Chile. This is the first record metamorphic Gosner 45 stage and the fourth georeferenced record of the species throughout its distribution. The data extend the presence of the species in the Biobío Region by more than 100 km, extending T. venustus to north of the Ralco Reserve. The presence of three metamorphic stage individuals and their coexistence with Alsodes sp. in this locality stands out.

The evolution of the Sesia Zone (Western Alps) from Carboniferous to Cretaceous: insights from zircon and allanite geochronology

Microscale dating of distinct domains in minerals that contain relics of multiple metamorphic events is a key tool to characterize the polyphase evolution of complex metamorphic terranes. Zircon and allanite from five metasediments and five metaintrusive high-pressure (HP) rocks from the Eclogite Micaschist Complex of the Sesia Zone were dated by SIMS and LA-ICP-MS. In the metasediments, zircon systematically preserves detrital cores and one or two metamorphic overgrowths. An early Permian age is obtained for the first zircon rim in metasediments from the localities of Malone Valley, Chiusella Valley and Monte Mucrone (292 ± 11, 278.8 ± 3.6 and 285.9 ± 2.9 Ma, respectively). In the Malone Valley and Monte Mucrone samples, the early Permian ages are attributed to high-temperature metamorphism and coincide with the crystallization ages of associated mafic and felsic intrusions. This implies that magmatism and metamorphism were coeval and associated to the same tectono-metamorphic extensional event. In the Malone Valley, allanite from a metasediment is dated at 241.1 ± 6.1 Ma and this age is tentatively attributed to a metasomatic/metamorphic event during Permo-Triassic extension. Outer zircon rims with a late Cretaceous age (67.4 ± 1.9 Ma) are found only in the micaschist from Monte Mucrone. In metagabbro of the Ivozio Complex, zircon cores yield an intrusive age for the protolith of 340.7 ± 6.8 Ma, whereas Alpine allanite are dated at 62.9 ± 4.2 and 55.3 ± 7.3 Ma. The Cretaceous ages constrain the timing of the HP metamorphic stage. The presence of zircon overgrowth only in the central area of the Eclogite Micaschist Complex is attributed to local factors such as (1) multiple fluid pulses at HP that locally enhanced zircon dissolution and recrystallization, and (2) slightly higher temperatures reached in this area during HP metamorphism.

Lamprophyres from Ospa ophiolite of the East Sayan (Russia)

<p>In Eastern Sayan mountains (E Siberia), ophiolite complexes form three extended branches: 1 - Ilchir (MOR ophiolites), 2 - Ospa-Khara-Nur (suprasubduction zone (SSZ) and volcanic arc (VA) ophiolites) and 3 - Shishkhid-Yehe-Shignin (back-arc ophiolites).</p><p>Lamprophyre (L) dykes or mica peridotites (Shestopalov, 1938) were found in brecciation zone of ophiolites (dunites, harzburgites, serpentinites) of the Ospa-Khara-Nur peridotite complex. They form bodies to 1m thick, and vein-like fragments in intensively deformed and altered (serpentinized, tremolitized) ultramafic rocks.</p><p>Dark gray massive porphyric L correspond to the range between ultramafic (UML), alkaline (AL), and Ca alkaline lamprophyre (CAL), and lamproite lamprophyres (LL) according to (Rock, 1991) and show compositional range in MgO-CaO, - Al<sub>2</sub>O<sub>3</sub>, - Na<sub>2</sub>O, - P<sub>2</sub>O<sub>5</sub> diagrams. Lamprophyre rocks consist of feldspar, phlogopite, orto- and clinopyroxene, amphibole, with relics of olivine (Fo=45-50, rarely 22-30) and large (up to 1 cm) porphyric phlogopite. In more acid L of CAL type with prevailing hypersthene and fieldspars are associated by amphiboles metasomatic type (ferro-eckermannite, actinolite, tremolite) and rarely metamorphic glaucophane. Micas grains from phlogopite to biotite (0.2-1.7% and 2.1-2.8% TiO<sub>2</sub>) are surrounded by sericite. Feldspar vary albite to anorthite, and rare grains of orthoclase and Ba-feldspar. Fluorine-apatite (Cl to 0.3%), ilmenite, rutile are common in L but zircon, monazite and Ce-La-epidote are rare. Mineral thermometry range from 1300<sup>o</sup>C to 950<sup>o</sup>C for LL then 850<sup>o</sup>C -560<sup>o</sup>C and low metamorphic stage.</p><p>TRE from L shows inclined REE with flat La-Sm, HFSE troughs but high LILE. The acid CL reveal Eu peak (Eu*=3,2; (La/Yb)<sub>n</sub>=9). Spider and REE diagram reveal elevated HFSE, Sr, Pb the same high LILE closer to anorthosites and pegmatiod charnokites. This suggests that high extremely high temperature ML reacted with acid rocks and produced Ca-alkaline L type.</p><p>Age spectra were obtained for phlogopites from lamprophyres by <sup>40</sup>Ar/<sup>39</sup>Ar step heating method. In sample VS-66-2, spectrum reveal intermediate plateaus of 3 stages (32%, 35%, 33%) of cumulative <sup>39</sup>Ar with ages 950 ± 6 and 976 ± 6 Ma, respectively. In the spectrum VS-57 a good plateau 902 ± 9 Ma is distinguished (79% of cumulative <sup>39</sup>Ar). Most discordant spectrum VS-52 reveals 4 stages of creation. Most likely the age of L formation is - 976 ± 6 Ma and corresponds to ocean stage. Most likely, and 902 ± 9 corresponds to the age of the intensive deformation later event in subduction zone. Further deformation suggests the complex tectonic-thermal history.</p><p>We suggest that late Proterozoic ophiolites which refer to oceanic stage of 1100 Ma were later incorporated to arc complex with the acid base. At 980 Ma they were subjected to plume event with the creation of UML due to reaction with crust and the they were hybridized with acid rocks to produce CAL. Late alteration produced series of secondary minerals. Thus the UML, and AL, and CAL give more information about the history of ophiolites of the Eastern Sayan.</p><p>This work supported by RFBR grants: No. 19-05-00764 and the Russian Ministry of Education and Science.</p><p>References:</p><ol><li>Shestopalov M.F. // In: Gemstone workbook. V. 4. 1938. P.84-100.</li> <li>Rock N.M.S. Lamprophyres. Springer Science+Business Media, LLC. 1991.</li> </ol>

Characterization and metamorphic evolution of Mesoproterozoic granulites from Sonapahar (Meghalaya), NE India, using EPMA monazite dating

This paper presents three different age domains, obtained by electron microprobe monazite dating, for granulitic gneisses collected from the Shillong-Meghalaya Gneissic Complex in Sonapahar, NE India, which contain radioactive materials, e.g. thorium (3.32–7.20 wt %), uranium (0.133–1.172 wt %) and lead (0.101–0.513 wt %). The microprobe analyses of monazite grains in the rock samples show that the monazites have three different ages ranging from Mesoproterozoic to Neoproterozoic. The oldest age (1571 ± 22 Ma) represents a peak metamorphic event, the youngest dominant age indicates the Pan-African tectonic event (478 ± 7 Ma) and the intermediate age marks the Grenvillian orogeny (1034 ± 91 Ma) or may be a mixing artefact; these ages are located at the cores, rims and intermediate parts of the monazite grains, respectively. The equilibrium mineral phases calculated for the granulitic gneisses from Sonapahar lie in a P–T range from 5.9 kbar/754 °C to 8.3 kbar/829 °C in the NCKFMASH system. Plotting the P–T conditions of the granulitic gneisses reveals a clockwise P–T path. Two major metamorphic events are observed in Sonapahar. The M1 metamorphic stage is represented by peak mineral assemblages of prograde garnet-forming reactions (8.2 kbar/∼713 °C) during Mesoproterozoic time (1571 ± 22 Ma). The M2 metamorphic stage featured decompression (3.9 kbar/∼701 °C) in which garnet–sillimanite broke down to form cordierite along an isothermal decompression path during the Pan-African tectonic event (478 ± 7 Ma).

Contrasting subduction–exhumation paths in the blueschists of the Anarak Metamorphic Complex (Central Iran)

The Anarak Metamorphic Complex, localized in Central Iran, is a fossil accretionary wedge composed of several tectonometamorphic units. Some of these, the Chah Gorbeh, the Morghab and the Ophiolitic complexes, contain mafic rocks that have been metamorphosed at high-pressure–low-temperature conditions. Such units have been stacked together and later refolded during the final stages of exhumation. Structural analysis at the mesoscale recognized at least three deformation events. Microstructural analyses, mineral chemistry and thermodynamic modelling reveal that the mafic schists followed contrasting P–T paths during their tectonometamorphic evolutions. In the schists of the Chah Gorbeh and Ophiolitic complexes an early greenschist-facies stage was later overprinted by blueschist-facies phase assemblages with suggested peak conditions of 390–440°C at 0.6–0.9 GPa for the meta-basalt within the Ophiolitic Complex and 320–380°C at 0.6–0.9 GPa for the blueschists of the Chah Gorbeh Complex. P–T conditions at metamorphic peak were 410–450°C at 0.78–0.9 GPa for the Morghab blueschists, but they are reached before a greenschist-facies re-equilibration. Compositional zoning of amphiboles and epidotes of this greenschist-facies stage suggests a renewed pressure increase at the end of this metamorphic stage. Based on these data we reconstructed a clockwise P–T path for the Morghab mafic schists and a counter-clockwise path for the Chah Gorbeh blueschists and ophiolitic meta-basalts. Such contrasting metamorphic evolutions of tectonic units that were later accreted to the same wedge are indicative of the complex tectonic dynamics that occur within accretionary–subduction complexes.