Molecular and genetic regulation of petal number variation in plants.

Floral forms with an increased number of petals, also known as double flower (DF) with great agronomic and economic values, have been selected and conserved in many domesticated plants, particularly in ornamentals. The molecular and genetic mechanisms that control this trait are therefore a hot topic, not only for scientists, but also for breeders. In this review, we summarize the current knowledge on the gene regulatory networks of flower initiation and development and known mutations that lead to variation of petal number in many species. Besides the well-accepted miR172/AP2-like module, for which many questions remain unanswered, we also discuss the current knowledge of other pathways in which mutations also lead to extra-petals formation, such as those involved in meristem development, hormones signaling, epigenetic regulations, and responses to environmental signals. We discuss how the concept of "natural mutants" and the recent advances in genomics and genome editing makes it possible to explore the molecular mechanisms underlying the DF formation, and how such knowledge could contribute to the future breeding and selection of this trait in more crops.

Genomes of Meniocus linifolius and Tetracme quadricornis reveal the ancestral karyotype and genomic features of core Brassicaceae.

Brassicaceae represents an important plant family from both a scientific and economic perspective. However, genomic features related to the early diversification of this family have not been fully characterized, especially upon the uplift of the Tibetan Plateau, which was followed by increasing aridity in the Asian interior, intensifying monsoons in Eastern Asia, and significantly fluctuating daily temperatures. Here, we reveal the genomic architecture that accompanied early Brassicaceae diversification by analyzing two high-quality chromosome-level genomes for Meniocus linifolius (Arabodae; clade D) and Tetracme quadricornis (Hesperodae; clade E), together with genomes representing all major Brassicaceae clades and the basal Aethionemeae. We reconstructed an ancestral core Brassicaceae karyotype (CBK) containing 9 pseudochromosomes with 65 conserved syntenic genomic blocks and identified 9702 conserved genes in Brassicaceae. We detected pervasive conflicting phylogenomic signals accompanied by widespread ancient hybridization events, which correlate well with the early divergence of core Brassicaceae. We identified a successive Brassicaceae-specific expansion of the class I TREHALOSE-6-PHOSPHATE SYNTHASE 1 (TPS1) gene family, which encodes enzymes with essential regulatory roles in flowering time and embryo development. The TPS1s were mainly randomly amplified, followed by expression divergence. Our results provide fresh insights into historical genomic features coupled with Brassicaceae evolution and offer a potential model for broad-scale studies of adaptive radiation under an ever-changing environment.

Effects of Sevoflurane and Propofol on Neurological Recovery of Traumatic Brain Injury Patients in the Early Postoperative Stage: A Retrospective Cohort Study.

Objective To investigate the effects of propofol and sevoflurane on neurological recovery of traumatic brain injury (TBI) patients in the early postoperative stage.Methods We retrospectively analyzed the clinical data of TBI patients who underwent craniotomy or decompressive craniectomy. Generalized additive mixed model (GAMM) was used to analyze effects of propofol and sevoflurane on Glasgow Coma Scale (GCS) on postoperative days 1, 3, and 7. Multivariate regression analysis was used to analyze effects of the two anesthetics on Glasgow Outcome Scale (GOS) at discharge.Results A total of 340 TBI patients were enrolled in this study. There were 110 TBI patients who underwent craniotomy including 75 in the propofol group and 35 in the sevoflurane group, and 134 patients who underwent decompressive craniectomy including 63 in the propofol group and 71 in the sevoflurane group. It showed no significant difference in GCS at admission between the propofol and the sevoflurane groups among craniotomy patients (ß = 0.75, 95%CI: -0.55 to 2.05, P = 0.260). However, elevation in GCS from baseline was 1.73 points (95%CI: -2.81 to -0.66, P = 0.002) less in the sevoflurane group than that in the propofol group on postoperative day 1, 2.03 points (95%CI: -3.14 to -0.91, P < 0.001) less on day 3, and 1.31 points (95%CI: -2.43 to -0.19, P = 0.022) less on day 7. The risk of unfavorable GOS (GOS 1, 2, and 3) at discharge was higher in the sevoflurane group (OR = 4.93, 95%CI: 1.05 to 23.03, P = 0.043). No significant difference was observed among two-group decompressive craniectomy patients in GCS and GOS.Conclusions Compared to propofol, sevoflurane was associated with worse neurological recovery during the hospital stay in TBI patients undergoing craniotomy. This difference was not detected in TBI patients undergoing decompressive craniectomy.

Complex and reticulate origin of edible roses (Rosa, Rosaceae) in China.

While roses are today among the most popular ornamental plants, the petals and fruits of some cultivars have flavored foods for millennia. The genetic origins of these edible cultivars remain poorly investigated. We collected the major varieties of edible roses available in China, assembled their plastome sequences, and phased the haplotypes for internal transcribed spacers (ITS1/ITS2) of the 18S-5.8S-26S nuclear ribosomal cistron. Our phylogenetic reconstruction using 88 plastid genomes, of primarily maternal origin, uncovered well-supported genetic relationships within Rosa, including all sections and all subgenera. We phased the ITS sequences to identify potential donor species ancestral to the development of known edible cultivars. The tri-parental Middle-Eastern origin of R. × damascena, the species most widely used in perfume products and food additives, was confirmed as a descendent of past hybridizations among R. moschata, R. gallica, and R. majalis/R. fedtschenkoana/R. davurica. In contrast, R. chinensis, R. rugosa, and R. gallica, in association with six other wild species, were the main donors for fifteen varieties of edible roses. The domesticated R. rugosa 'Plena' was shown to be a hybrid between R. rugosa and R. davurica, sharing a common origin with R. 'Fenghua'. Only R. 'Jinbian' and R. 'Crimson Glory' featured continuous flowering. All remaining cultivars of edible roses bloomed only once a year. Our study provides important resources for clarifying the origin of edible roses and suggests a future for breeding new cultivars with unique traits, such as continuous flowering.

Effects of chrysophanol on hippocampal damage and mitochondrial autophagy in mice with cerebral ischemia reperfusion.

OBJECTIVE: The cerebral ischemia-reperfusion (I/R) model is crucial for the study of cerebral stroke. Chrysophanol (Chry) can protect nerve damage of mice in cerebral ischemia-reperfusion injury. This study aimed at investigating the neuroprotective effects of chrysophanol through mitochondrial autophagy in mice with ischemia-reperfusion injury. MATERIALS AND METHODS: Adult mice were stochastically divided into five groups: sham, I/R (solvent), I/R+Chry (dose, 10.0ml/kg), I/R+Chry (dose, 1.0ml/kg), and I/R+Chry (dose, 0.1ml/kg). The cerebral ischemia-reperfusion model was made in I/R and I/R+Chry groups. The changes in hippocampal formation were observed by hematoxylin and eosin (H&E) staining. The expressions of LC3B-II and LC3B-I protein in hippocampus were demonstrated by western blot (WB). The fluorescence intensities of NIX, LC3B, and mitochondria were detected by immunohistochemistry fluorescent (IF). RESULTS: Comparing with the I/R group, the I/R+Chry groups showed improvements in reducing the damage on the hippocampus, indicated by the reduced ratio of LC3B-II and LC3B-I protein, decreased fluorescence intensity of NIX and LC3B, and increased intensity of mitochondrial fluorescence. CONCLUSION: Our study showed that chrysophanol may regulate mitochondrial autophagy through NIX protein and alleviate the damage of hippocampus through decreasing the level of mitochondrial autophagy.

Expansion and expression diversity of FAR1/FRS-like genes provides insights into flowering time regulation in roses.

Roses are important horticultural plants with enormous diversity in flowers and flowering behavior. However, molecular regulation of flowering time variation in roses remains poorly characterized. Here, we report an expansion of the FAR1/FRS-like genes that correlates well with the switch to prostrate-to-erect growth of shoots upon flowering in Rosa wichuraiana 'Basye's Thornless' (BT). With the availability of the high-quality chromosome-level genome assembly for BT that we developed recently, we identified 91 RwFAR1/FRS-like genes, a significant expansion in contrast to 52 in Rosa chinensis 'Old Blush' (OB), a founder genotype in modern rose domestication. Rose FAR1/FRS-like proteins feature distinct variation in protein domain structures. The dispersed expansion of RwFAR1/FRS-like genes occurred specifically in clade I and II and is significantly associated with transposon insertion in BT. Most of the RwFAR1/FRS-like genes showed relatively higher expression level than their corresponding orthologs in OB. FAR1/FRS-like genes regulate light-signaling processes, shade avoidance, and flowering time in Arabidopsis thaliana. Therefore, the expansion and duplication of RwFAR1/FRS-like genes, followed by diversification in gene expression, might offer a novel leverage point for further understanding the molecular regulation of the variation in shoot-growth behavior and flowering time in roses.

Association between neutrophil-to-lymphocyte ratio and major postoperative complications after carotid endarterectomy: A retrospective cohort study.

BACKGROUND: Carotid artery cross-clamping during carotid endarterectomy (CEA) may damage local cerebral perfusion and induce cerebral ischemia-reperfusion injury to activate local inflammatory responses. Neutrophil-to-lymphocyte ratio (NLR) is an indicator that reflects systemic inflammation. However, the correlation between NLR and complications after CEA remains unclear. AIM: To investigate the association between NLR and major complications after surgery in patients undergoing CEA. METHODS: This retrospective cohort study included patients who received CEA between January 2016 and July 2018 at Beijing Tiantan Hospital. Neutrophil and lymphocyte counts in whole blood within 24 h after CEA were collected. The primary outcome was the composite of major postoperative complications including neurological, pulmonary, cardiovascular and acute kidney injuries. The secondary outcomes included infections, fever, deep venous thrombosis, length of hospitalization and cost of hospitalization. Statistical analyses were performed using EmpowerStats software and R software. RESULTS: A total of 224 patients who received CEA were screened for review and 206 were included in the statistical analyses; of whom, 40 (19.42%) developed major postoperative complications. NLR within 24 h after CEA was significantly correlated with major postoperative complications (P = 0.026). After confounding factors were adjusted, the odds ratio was 1.15 (95%CI: 1.03-1.29, P = 0.014). The incidence of major postoperative complications in the high NLR group was 8.47 times that in the low NLR group (P = 0.002). CONCLUSION: NLR is associated with major postoperative complications in patients undergoing CEA.

Rose without prickle: genomic insights linked to moisture adaptation.

Prickles act against herbivores, pathogens or mechanical injury, while also preventing water loss. However, whether prickles have new function and the molecular genetics of prickle patterning remain poorly explored. Here, we generated a high-quality reference genome assembly for 'Basye's Thornless' (BT), a prickle-free cultivar of Rosa wichuraiana, to identify genetic elements related to stem prickle development. The BT genome harbors a high level of sequence diversity in itself and with cultivar 'Old Blush' (R. chinensis), a founder genotype in rose domestication. Inheritance of stem prickle density was determined and two QTL were identified. Differentially expressed genes in QTL were involved in water-related functions, suggesting that prickle density may hitchhike with adaptations to moist environments. While the prickle-related gene-regulatory-network (GRN) was highly conserved, the expression variation of key candidate genes was associated with prickle density. Our study provides fundamental resources and insights for genome evolution in the Rosaceae. Ongoing efforts on identification of the molecular bases for key rose traits may lead to improvements for horticultural markets.

Genome-wide identification of WD40 genes reveals a functional diversification of COP1-like genes in Rosaceae.

KEY MESSAGE: Genome-wide identification of WD40-like genes reveals a duplication of COP1-like genes, one of the key players involved in regulation of flowering time and photomorphogenesis, with strong functional diversification in Rosaceae. WD40 proteins play crucial roles in a broad spectrum of developmental and physiological processes. Here, we conducted a systematic characterization of this family of genes in Rosa chinensis 'Old Blush' (OB), a founder genotype for modern rose domestication. We identified 187 rose WD40 genes and classified them into 5 clusters and 15 subfamilies with 11 of RcWD40s presumably generated via tandem duplication. We found RcWD40 genes were expressed differentially following stages of vegetative and reproductive development. We detected a duplication of CONSTITUTIVE PHOTOMORPHOGENIC1-like genes in rose (RcCOP1 and RcCOP1L) and other Rosaceae plants. Featuring a distinct expression pattern and a different profile of cis-regulatory-elements in the transcriptional regulatory regions, RcCOP1 seemed being evolutionarily conserved while RcCOP1L did not dimerize with RcHY5 and RcSPA4. Our data thus reveals a functional diversification of COP1-like genes in Rosacaeae plants, and provides a valuable resource to explore the potential function and evolution of WD40-like genes in Rosaceae plants.

The complete chloroplast genome sequence of a rambler rose, Rosa wichuraiana (Rosaceae).

The rambler Rosa wichuraiana Crép. is an important founder species during modern rose domestication. However, the chloroplast genome (plastome) of this wild species remains unavailable. Here, we assembled the complete chloroplast genomes for two genotypes of R. wichuraiana. Both plastomes were typical quadripartite circular with 156,500/156,504 bp in length, comprising a large single-copy (LSC) region of 85,651/85,660 bp and a small single-copy (SSC) region of 18,751/18,744 bp, separated by two inverted repeat (IR) regions of 26,049/26,050 bp, respectively. Both plastomes encoded 113 unique genes, including 79 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Phylogenetic reconstruction with several rose plastomes revealed that both genotypes were sisters to a clade including Rosa luciae, Rosa multiflora, and Rosa maximowicziana.