Multilayered synergistic regulation of phytoalexin biosynthesis by ethylene, jasmonate, and MAPK signaling pathways in Arabidopsis.

Camalexin, an indolic antimicrobial metabolite, is the major phytoalexin in Arabidopsis thaliana, and plays a crucial role in pathogen resistance. Our previous studies revealed that the Arabidopsis mitogen-activated protein kinases MPK3 and MPK6 positively regulate pathogen-induced camalexin biosynthesis via phosphoactivating the transcription factor WRKY33. Here, we report that the ethylene and jasmonate (JA) pathways act synergistically with the MPK3/MPK6-WRKY33 module at multiple levels to induce camalexin biosynthesis in Arabidopsis upon pathogen infection. The ETHYLENE RESPONSE FACTOR1 (ERF1) transcription factor integrates the ethylene and JA pathways to induce camalexin biosynthesis via directly upregulating camalexin biosynthetic genes. ERF1 also interacts with and depends on WRKY33 to upregulate camalexin biosynthetic genes, indicating that ERF1 and WRKY33 form transcriptional complexes to cooperatively activate camalexin biosynthetic genes, thereby mediating the synergy of ethylene/JA and MPK3/MPK6 signaling pathways to induce camalexin biosynthesis. Moreover, as an integrator of the ethylene and JA pathways, ERF1 also acts as a substrate of MPK3/MPK6, which phosphorylate ERF1 to increase its transactivation activity and therefore further cooperate with the ethylene/JA pathways to induce camalexin biosynthesis. Taken together, our data reveal the multilayered synergistic regulation of camalexin biosynthesis by ethylene, JA, and MPK3/MPK6 signaling pathways via ERF1 and WRKY33 transcription factors in Arabidopsis.

Differential modulation of C. elegans motor behavior by NALCN and two-pore domain potassium channels.

Two-pore domain potassium channels (K2P) are a large family of "background" channels that allow outward "leak" of potassium ions. The NALCN/UNC80/UNC79 complex is a non-selective channel that allows inward flow of sodium and other cations. It is unclear how K2Ps and NALCN differentially modulate animal behavior. Here, we found that loss of function (lf) in the K2P gene twk-40 suppressed the reduced body curvatures of C. elegans NALCN(lf) mutants. twk-40(lf) caused a deep body curvature and extended backward locomotion, and these phenotypes appeared to be associated with neuron-specific expression of twk-40 and distinct twk-40 transcript isoforms. To survey the functions of other less studied K2P channels, we examined loss-of-function mutants of 13 additional twk genes expressed in the motor circuit and detected defective body curvature and/or locomotion in mutants of twk-2, twk-17, twk-30, twk-48, unc-58, and the previously reported twk-7. We generated presumptive gain-of-function (gf) mutations in twk-40, twk-2, twk-7, and unc-58 and found that they caused paralysis. Further analyses detected variable genetic interactions between twk-40 and other twk genes, an interdependence between twk-40 and twk-2, and opposite behavioral effects between NALCN and twk-2, twk-7, or unc-58. Finally, we found that the hydrophobicity/hydrophilicity property of TWK-40 residue 159 could affect the channel activity. Together, our study identified twk-40 as a novel modulator of the motor behavior, uncovered potential behavioral effects of five other K2P genes and suggests that NALCN and some K2Ps can oppositely affect C. elegans behavior.

Exploring transvaginal sonographic characteristics of the levator ani muscle in women with postpartum pelvic floor myofascial pain.

BACKGROUND: Pelvic floor myofascial pain is one of the pelvic floor dysfunction diseases disturbing women after delivery. There is a lack of objective standardization for the diagnosis of pelvic floor myofascial pain due to the various symptoms and the dependence on the palpating evaluation. Ultrasound imaging has the advantages of safety, simplicity, economy and high resolution, which makes it an ideal tool for the assistant diagnosis of pelvic floor myofascial pain and evaluation after treatment. METHODS: This is a retrospective case-control study including women accepting evaluation of pelvic floor function at 6 weeks to 1 year postpartum. They were divided into pelvic floor myofascial pain group and normal control group. A BCL 10-5 biplane transducer was applied to observed their puborectalis. The length, minimum width, area, deficiency, deficiency length, deficiency width, deficiency area, rate of deficiency area, local thickening,angle between the tendinous arch of levator ani muscle and puborectalis of corresponding puborectalis in different groups were observed and measured. RESULTS: A total of 220 postpartum women participated in the study, with 77 in the pelvic floor myofascial pain group and 143 in the normal control group. The Intraclass correlation coefficient value was over 0.750, and Kappa ranged from 0.600 to 0.800. puborectalis deficiency (adjusted odds ratio = 11.625, 95% confidence interval = 4.557-29.658) and focal thickening (adjusted odds ratio = 16.891, 95% confidence interval = 1.819-156.805) were significantly associated with higher odds of having postpartum pelvic floor myofascial pain. Grayscale or the angle between the arch tendineus levator ani and puborectalis measurements on the pain side tended to be smaller than on the non-pain side in patients with unilateral puborectalis or iliococcygeus pain (P < 0.05). CONCLUSIONS: This study demonstrated that transvaginal ultrasound was a potentially efficient technique for evaluating postpartum pelvic floor myofascial pain due to its ability to assess various sonographic characteristics of the levator ani muscles.

Tape Tarsorrhaphy in the Management of Lagophthalmos Caused by Severe Congenital Blepharoptosis Procedures.

BACKGROUND: Lagophthalmos, a common complication after blepharoptosis correction, has plagued oculoplastic surgeons. The goal of this study was to investigate the effect of tape eyelid closure on reducing the occurrence of lagophthalmos after blepharoptosis correction. METHODS: From April 2020 to June 2021, a total of 112 patients with severe congenital ptosis received corrective surgery at the Department of Plastic and Reconstructive Surgery, Xijing Hospital, Fourth Military Medical University. Of these, 48 underwent frontalis muscle advancement technique and 64 underwent conjoint fascial sheath suspension. Preoperative data collected included demographics, levator function, Bell's phenomenon, and marginal reflex distance 1 (MRD1). Postoperative data included surgery type, MRD1, eyelid closure function, aesthetic outcomes (including eyelid contour, eyelid symmetry, and eyelid crease), keratitis, and other complications. RESULTS: Frontalis muscle advancement technique group: the median of safe eye closure time was 7.3 months (positive Bell's phenomenon; interquartile range [IQR], 3.8-10.8 months) and 13.9 months (poor Bell's phenomenon; IQR, 11.6-16.1 months). There was a significant improvement between the preoperative and postoperative MRD1 (-1.52 ± 0.82 vs 3.85 ± 0.58 mm, P < 0.05). Conjoint fascial sheath suspension group: the median of safe eye closure time was 5.7 months (positive Bell's phenomenon; IQR, 2.9-8.5 months) and 12.4 months (poor Bell's phenomenon; IQR, 8.1-16.7 months). There was a significant improvement between the preoperative and postoperative MRD1 (-1.02 ± 0.91 vs 4.15 ± 1.03 mm, P < 0.05). All patients/guardians were satisfied with the aesthetic outcomes. CONCLUSIONS: Tape tarsorrhaphy is a safe, easy-to-learn method for treating lagophthalmos with a good aesthetic outcome.

The Aesthetic Evaluation of the Brow-Eye Continuum After Correction of Severe Congenital Ptosis in Children With Extended Frontalis Muscle Advancement Technique.

BACKGROUND: Severe congenital ptosis is a common ocular deformity in pediatric patients that can significantly impact visual development and aesthetic appearance, leading to negative psychosocial outcomes. The frontalis muscle advancement technique is a well-established surgical treatment for severe congenital ptosis. Aesthetic changes of the brow-eye continuum often plays an important role in ptosis surgery. METHODS: We conducted a single-center retrospective case series study of patients with severe congenital ptosis who underwent the frontalis muscle advancement technique at the Department of Plastic and Reconstructive Surgery, Xijing Hospital, Fourth Military Medical University between April 2020 and June 2021. The study aimed to evaluate the aesthetic changes of the eyebrow-eyelid continuum after surgery. The main outcome measurements included marginal reflex distance 1, palpebral fissure height, eyebrow position, upper eyelid to lower eyebrow distance, lower eyelid to upper eyebrow distance, and nasal base to lower eyelid distance. RESULTS: The study included 48 patients (66 eyelids), with 30 unilateral and 18 bilateral patients. Our analysis found that eyebrow height decreased by an average of 4.8% postoperatively relative to preoperatively in all patients. CONCLUSIONS: The frontalis muscle advancement technique has demonstrated effectiveness in achieving aesthetically pleasing outcomes in children with severe ptosis. It is crucial to pay careful attention to the brow-eye continuum during the correction process, as its harmony can greatly impact the final result.

Tape Eyelid Closure: An Effective Solution for Nocturnal Lagophthalmos in Patients with Ptosis and Poor Bell's Phenomenon.

BACKGROUND: Poor Bell's phenomenon is often considered a relative contraindication for ptosis surgery, as it increases the risk of corneal exposure and dry eye symptoms after surgery. However, the Bell's phenomenon may vary in different individuals and sleep stages, making it inaccurate to predict the position of the eye during sleep based on awake examination. This study aimed to investigate the role of Bell's phenomenon in ptosis surgery and the management of nocturnal lagophthalmos. METHODS: We conducted a retrospective case series of 23 patients with ptosis and poor Bell's phenomenon who underwent different surgical techniques at Xijing Hospital from April 2020 to June 2021. We assessed Bell's phenomenon at different stages of sleep and collected data on ptosis degree, surgical approach, lagophthalmos, complications, and outcomes. RESULTS: Of the total 23 patients originally considered for study, 9 with frontalis muscle advancement technique, 8 with conjoint fascial sheath suspension, 4 with levator resection technique, and 2 with levator aponeurosis plication technique. All patients achieved satisfactory correction of ptosis. One patient had prolonged lagophthalmos and underwent reoperation to lower the eyelid height. Other complications were minor and resolved with conservative treatment. CONCLUSION: We conclude that poor Bell's phenomenon is not a relative contraindication for ptosis surgery. Nocturnal lagophthalmos should be monitored after ptosis surgery regardless of the Bell's phenomenon results. Tape eyelid closure can be an effective solution to protect the corneal surface during nocturnal lagophthalmos. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266 .

An EPFL peptide signaling pathway promotes stamen elongation via enhancing filament cell proliferation to ensure successful self-pollination in Arabidopsis thaliana.

Proper stamen filament elongation is essential for plant self-pollination and reproduction. Several phytohormones such as jasmonate and gibberellin play important roles in controlling filament elongation, but other endogenous signals involved in this developmental process remain unknown. We report here that three EPIDERMAL PATTERNING FACTOR-LIKE (EPFL) family peptides, EPFL4, EPFL5 and EPFL6, act redundantly to promote stamen filament elongation via enhancing filament cell proliferation in Arabidopsis thaliana. Knockout of EPFL4-6 genes led to shortened filaments due to defective filament cell proliferation, resulting in pollination failure and male sterility. Further genetic and biochemical analyses indicated that the ERECTA family and the SOMATIC EMBRYOGENESIS RECEPTOR KINASE (SERK) family RLKs form receptor complexes to perceive EPFL4-6 peptides and promote filament cell proliferation. Moreover, based on both loss- and gain-of-function genetic analyses, the mitogen-activated protein kinase cascade MKK4/MKK5-MPK6 was shown to function downstream of EPFL4-6 to positively regulate cell proliferation in stamen filaments. Together, this study reveals that an EPFL peptide signaling pathway composed of the EPFL4-6 peptide ligands, the ERECTA-SERK receptor complexes and the downstream MKK4/MKK5-MPK6 cascade promotes stamen filament elongation via enhancing filament cell proliferation to ensure successful self-pollination and normal fertility in Arabidopsis.

Differential Phosphorylation of the Transcription Factor WRKY33 by the Protein Kinases CPK5/CPK6 and MPK3/MPK6 Cooperatively Regulates Camalexin Biosynthesis in Arabidopsis.

Camalexin is a major phytoalexin that plays a crucial role in disease resistance in Arabidopsis (Arabidopsis thaliana). We previously characterized the regulation of camalexin biosynthesis by the mitogen-activated protein kinases MPK3 and MPK6 and their downstream transcription factor WRKY33. Here, we report that the pathogen-responsive CALCIUM-DEPENDENT PROTEIN KINASE5 (CPK5) and CPK6 also regulate camalexin biosynthesis in Arabidopsis. Chemically induced expression of constitutively active CPK5 or CPK6 variants was sufficient to induce camalexin biosynthesis in transgenic Arabidopsis plants. Consistently, the simultaneous mutation of CPK5 and CPK6 compromised camalexin production in Arabidopsis induced by the fungal pathogen Botrytis cinerea Moreover, we identified that WRKY33 functions downstream of CPK5/CPK6 to activate camalexin biosynthetic genes, thereby inducing camalexin biosynthesis. CPK5 and CPK6 interact with WRKY33 and phosphorylate its Thr-229 residue, leading to an increase in the DNA binding ability of WRKY33. By contrast, the MPK3/MPK6-mediated phosphorylation of WRKY33 on its N-terminal Ser residues enhances the transactivation activity of WRKY33. Furthermore, both gain- and loss-of-function genetic analyses demonstrated the cooperative regulation of camalexin biosynthesis by CPK5/CPK6 and MPK3/MPK6. Taken together, these findings indicate that WRKY33 functions as a convergent substrate of CPK5/CPK6 and MPK3/MPK6, which cooperatively regulate camalexin biosynthesis via the differential phospho-regulation of WRKY33 activity.

Modified Levator Resection Technique for Moderate Congenital Blepharoptosis.

BACKGROUND: For moderate ptosis associated with fair levator function (LF), the levator resection is the most commonly used procedure. However, the levator resection technique still has some disadvantages, such as residual lagophthalmos (RL), undercorrection, conjunctival prolapse, and eyelid contour abnormality. To solve the above problems, our team have made modifications to the levator resection technique in three aspects: releasing the levator muscle sufficiently, preserving the supporting structure of the conjunctiva, and placing multiple suture sites. METHODS: Fifty-seven patients (81 eyes) underwent the modified levator resection technique and were enrolled in the study. Preoperative data collected included age, sex, margin reflex distance 1 (MRD1), and LF. Postoperative data collected included MRD1, RL, patient satisfaction, complications, and length of follow-up. RESULTS: Mean MRD1 significantly increased from 1.45 ± 0.65 mm preoperatively to 3.57 ± 0.51 mm postoperatively. Mean LF significantly increased from 6.49 ± 1.12 mm preoperatively to 9.48 ± 1.39 mm postoperatively. Successful correction was obtained in 77 eyes (95.1%). Mean RL was 1.09 ± 0.57 and 72 eyes (88.9%) showed excellent or good eyelid closure function. Fifty-four patients (94.7%) were completely satisfied with the final result. Complications such as hematoma, infection, conjunctival prolapse, suture exposure, corneal abrasion, and keratitis were not found in any cases during follow-up. CONCLUSION: This modified levator resection technique introduced in this study is effective in correcting moderate congenital blepharoptosis, while minimizing RL, undercorrection, conjunctival prolapse, eyelid contour abnormality by releasing the levator muscle sufficiently, preserving the supporting structure of the conjunctiva, and placing multiple suture sites. LEVEL OF EVIDENCE IV: This journal requires that authors 42 assign a level of evidence to each article. For a full 43 description of these Evidence-Based Medicine ratings, 44 please refer to the Table of Contents or the online 45 Instructions to Authors www.springer.com/00266 .

The Arabidopsis Pleiotropic Drug Resistance Transporters PEN3 and PDR12 Mediate Camalexin Secretion for Resistance to Botrytis cinerea.

Plant defense often depends on the synthesis and targeted delivery of antimicrobial metabolites at pathogen contact sites. The pleiotropic drug resistance (PDR) transporter PENETRATION3 (PEN3)/PDR8 in Arabidopsis (Arabidopsis thaliana) has been implicated in resistance to a variety of fungal pathogens. However, the antimicrobial metabolite(s) transported by PEN3 for extracellular defense remains unidentified. Here, we report that PEN3 functions redundantly with another PDR transporter (PDR12) to mediate the secretion of camalexin, the major phytoalexin in Arabidopsis. Consistent with this, the pen3 pdr12 double mutants exhibit dramatically enhanced susceptibility to the necrotrophic fungus Botrytis cinerea as well as severe hypersensitivity to exogenous camalexin. PEN3 and PDR12 are transcriptionally activated upon B. cinerea infection, and their expression is regulated by the mitogen-activated protein kinase 3 (MPK3) and MPK6, and their downstream WRKY33 transcription factor. Further genetic analysis indicated that PEN3 and PDR12 contribute to B. cinerea resistance through exporting not only camalexin but also other unidentified metabolite(s) derived from Trp metabolism, suggesting that PEN3 and PDR12 have multiple functions in Arabidopsis immunity via transport of distinct Trp metabolic products.

Aesthetic Changes of Brow-Eyelid Continuum After Correction of Moderate-Severe Blepharoptosis with Conjoint Fascial Sheath Suspension.

BACKGROUND: As periorbital aesthetic commonly improved in blepharoptosis patients after correction surgery, the aim of this study was to elaborate the brow-eyelid continuum changes in moderate-severe ptosis patients who underwent conjoint fascial sheath suspension systematically. METHODS: Patients with moderate-severe ptosis who underwent conjoint fascial sheath suspension were assessed by using pre- and post-operative digital photographs in the primary gaze position of the eye. The main outcome measurements included marginal reflex distance1 (MRD1), palpebral fissure height (PFH), eyebrow position, the symmetry of face and the horizontal forehead lines condition. RESULTS: There were 43 patients (53 eyelids) in our study, including 33 unilateral and 10 bilateral patients. The mean levator function was 3.00 ± 1.07 mm. Before surgery, the mean MRD1 and PFH were 0.60 ± 1.14 mm and 6.75 ± 1.71 mm, respectively. The mean eyebrow height at medial, center, lateral position was 33.16 ± 3.95 mm, 35.99 ± 4.02 mm and 34.35 ± 4.80 mm, respectively. It was found that MRD1 and PFH symmetry both were 23.26% and eyebrow symmetry was 62.79%. For forehead wrinkles, 48.84% of the patients was mild, 34.88% was moderate, and 16.28% was severe. The average follow-up was 12.78 months (ranged from 12 to 18 months). One month after surgery, the mean MRD1 and PFH were 5.68 ± 0.86 mm, 11.61 ± 0.97 mm, respectively, both of which improved significantly (P < 0.0001). The mean eyebrow height at medial, center, lateral position descended to 28.22 ± 4.77 mm (P = 0.017), 31.41 ± 4.58 mm (P = 0.033) and 30.28 ± 3.41 mm (P = 0.018), respectively. The result showed that the rate of patients with MRD1 symmetry was 32.56%, PFH symmetry was 30.23%, and eyebrow symmetry was 90.7%. For forehead wrinkles, 69.77% was mild and 30.23% was moderate. Then, patients' eyebrow gradually elevated, while their upper eyelid dropped. At the last follow-up, the mean MRD1 and PFH were 3.83 ± 0.98 mm and 9.84 ± 1.56 mm, respectively. The mean eyebrow height at medial, center, lateral position improved to 30.52 ± 4.59 mm (P = 0.031), 32.40 ± 4.68 mm (P = 0.033), 31.19 ± 4.16 mm (P = 0.028), respectively. The patients with MRD1 symmetry accounted for 86.05%, PFH symmetry 86.05%, and eyebrow symmetry 90.7%. For forehead wrinkles, 67.44% was mild and 32.56% was moderate. CONCLUSION: CFS suspension can effectively reconstruct moderate-severe ptosis patients' aesthetics of the brow-eyelid continuum by descending elevated eyebrow, improving facial symmetry and reducing forehead rhytids. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Perception of the pathogen-induced peptide RGF7 by the receptor-like kinases RGI4 and RGI5 triggers innate immunity in Arabidopsis thaliana.

Signaling peptides play crucial roles in plant growth, development and defense. We report here that the Arabidopsis thaliana secreted peptide, ROOT MERISTEM GROWTH FACTOR 7 (RGF7), functions as an endogenous elicitor to trigger plant immunity. Expression of the RGF7 precursor-encoding gene (preRGF7) is highly induced in Arabidopsis leaves upon infection by the bacterial pathogen Pseudomonas syringae. The pathogen-responsive preRGF7 expression is regulated by the transcription factor WRKY33 and its upstream mitogen-activated protein kinases MPK3/MPK6 and calcium-dependent protein kinases CPK5/CPK6. In the absence of pathogen attack, chemically induced expression of preRGF7 in transgenic Arabidopsis plants was sufficient to trigger immune responses. Pre-induction of preRGF7 expression in transgenic Arabidopsis also led to enhanced immune responses and increased resistance to P. syringae infection. Biochemical and genetic analyses demonstrated that RGF7 is perceived by the leaf-expressed RGF1 INSENSITIVE (RGI) family receptors RGI4 and RGI5. The SOMATIC EMBRYOGENESIS RECEPTOR KINASES (SERKs) BAK1 and SERK4 are also involved in RGF7 perception via forming RGF7-induced receptor-complexes with RGI4 and RGI5. These results indicate that the pathogen-induced RGF7 peptide, perceived by the RGI4/RGI5-BAK1/SERK4 receptor complexes, acts as a new damage-associated molecular pattern (DAMP) and plays a significant role in Arabidopsis immunity.

Conjugation of Hemoglobin and Mannan Markedly Improves the Immunogenicity of Domain III of the Zika Virus E Protein: Structural and Immunological Study.

Zika virus (ZIKV) leads to congenital microcephaly and anomalies and severe neurological diseases such as Guillain-Barre syndrome. Safe and effective vaccines are necessitated to deal with these severe health threats. As an ideal antigen, the domain III of the envelope protein (EDIII) of ZIKV can evoke potent neutralizing antibodies without any antibody-dependent enhancement (ADE) effect. However, EDIII necessitates to be formulated with an antigen delivery system or adjuvants to improve its immunogenicity. Hemoglobin (Hb) regulates inflammation, cytokine levels, and activate macrophage. Mannan is a polysaccharide of the fungal cell wall with an immunomodulatory activity. In this study, EDIII was conjugated with Hb and mannan, using the disulfide bond as the linker. Hb and mannan both functioned as the adjuvants. Conjugation of Hb and mannan acted as the delivery system for EDIII. The structure of EDIII was essentially maintained upon conjugation of Hb and mannan. The intracellular release of EDIII from the conjugate (HM-EDIII-2) was achieved by reduction of the glutathione-sensitive disulfide bond. As compared with EDIII, HM-EDIII-2 elicited high EDIII-specific IgG titers and high levels of Th1-type cytokines (IFN-γ and IL-2) and Th2-type cytokines (IL-5 and IL-10), along with no apparent toxicity to the organs. Moreover, the pharmacokinetic study revealed a prolonged serum exposure of HM-EDIII-2 to the immune cells. Thus, HM-EDIII-2 could boost a strong humoral and cellular immune response to EDIII. Our study was expected to provide the feasibility necessary to develop a robust and potentially safe ZIKV vaccine.

First-principles calculations on the resistance and electronic properties of H2 adsorption on a CoO-SnO2 heterojunction surface.

Compared with pure metal oxides, heterojunctions greatly change the response to gas by the synergistic effect of the interface. In this work, density functional theory was used to reveal the adsorption performance of H2 on the heterojunction under oxygen conditions. First, we determined the most reasonable heterojunction structure based on the adhesion work. According to the adsorption energy, the presence of SnO2(100)(I)/CoO(110)(II) made the adsorption of H2 more stable. The DOS results showed that the resistance of the heterojunction increased with H2 adsorption, following the same trend as that of CoO(110) with H2 adsorption, although that of the heterojunction increased more. The electron density and electron density difference indicated that the heterojunction improved the reaction between H2 and oxygen ions on CoO(110). However, the resistance of CoO(110)(II)/SnO2(100)(II) increased after H2 adsorption, contrary to the resistance change of SnO2(100). Besides, the bonding energy between H2 and the adsorption site became worse. The above results demonstrated that the presence of the heterojunction could indeed change the response trend and the adsorption behavior of H2. Interestingly, the adsorption sites and effects of H2 were different when two metal oxides were used as the substrate of the heterojunction, respectively.

Plant cell surface receptor-mediated signaling - a common theme amid diversity.

Sessile plants employ a diverse array of plasma membrane-bound receptors to perceive endogenous and exogenous signals for regulation of plant growth, development and immunity. These cell surface receptors include receptor-like kinases (RLKs) and receptor-like proteins (RLPs) that harbor different extracellular domains for perception of distinct ligands. Several RLK and RLP signaling pathways converge at the somatic embryogenesis receptor kinases (SERKs), which function as shared co-receptors. A repertoire of receptor-like cytoplasmic kinases (RLCKs) associate with the receptor complexes to relay intracellular signaling. Downstream of the receptor complexes, mitogen-activated protein kinase (MAPK) cascades are among the key signaling modules at which the signals converge, and these cascades regulate diverse cellular and physiological responses through phosphorylation of different downstream substrates. In this Review, we summarize the emerging common theme that underlies cell surface receptor-mediated signaling pathways in Arabidopsisthaliana: the dynamic association of RLKs and RLPs with specific co-receptors and RLCKs for signal transduction. We further discuss how signaling specificities are maintained through modules at which signals converge, with a focus on SERK-mediated receptor signaling.

Cellulase-Assisted Extraction of Polysaccharides from White Hyacinth Bean: Characterization of Antioxidant Activity and Promotion for Probiotics Proliferation.

Food-derived polysaccharides have advantages over synthetical compounds and have attracted interest globally for decades. In this study, we optimized the cellulase-assisted extraction of polysaccharides from white hyacinth bean (PWBs) with the aid of response surface methodology (RSM). The optimum extraction parameters were a pH of 7.79, a cellulase of 2.73%, and a ratio of water to material of 61.39, producing a high polysaccharide yield (3.32 ± 0.03)%. The scavenging ability of PWBs varied on three radicals (hydroxyl > 2,2-diphenyl-1-picrylhydrazyl (DPPH) > superoxide). Furthermore, PWBs contributed to the proliferation of three probiotic bacteria (Lactobacillus acidophilus LA5, Bifidobacterium bifidum BB01, and Lactobacillus bulgaricus LB6). These investigations of PWBs provide a novel bioresource for the exploitation of antioxidant and probiotic bacterial proliferation.

Phosphorylation of an ERF transcription factor by Arabidopsis MPK3/MPK6 regulates plant defense gene induction and fungal resistance.

Arabidopsis thaliana MPK3 and MPK6, two mitogen-activated protein kinases (MAPKs or MPKs), play critical roles in plant disease resistance by regulating multiple defense responses. Previously, we characterized the regulation of phytoalexin biosynthesis by Arabidopsis MPK3/MPK6 cascade and its downstream WRKY33 transcription factor. Here, we report another substrate of MPK3/MPK6, ETHYLENE RESPONSE FACTOR6 (ERF6), in regulating Arabidopsis defense gene expression and resistance to the necrotrophic fungal pathogen Botrytis cinerea. Phosphorylation of ERF6 by MPK3/MPK6 in either the gain-of-function transgenic plants or in response to B. cinerea infection increases ERF6 protein stability in vivo. Phospho-mimicking ERF6 is able to constitutively activate defense-related genes, especially those related to fungal resistance, including PDF1.1 and PDF1.2, and confers enhanced resistance to B. cinerea. By contrast, expression of ERF6-EAR, in which ERF6 was fused to the ERF-associated amphiphilic repression (EAR) motif, strongly suppresses B. cinerea-induced defense gene expression, leading to hypersusceptibility of the ERF6-EAR transgenic plants to B. cinerea. Different from ERF1, the regulation and function of ERF6 in defensin gene activation is independent of ethylene. Based on these data, we conclude that ERF6, another substrate of MPK3 and MPK6, plays important roles downstream of the MPK3/MPK6 cascade in regulating plant defense against fungal pathogens.

A MAPK cascade downstream of ERECTA receptor-like protein kinase regulates Arabidopsis inflorescence architecture by promoting localized cell proliferation.

Spatiotemporal-specific cell proliferation and cell differentiation are critical to the formation of normal tissues, organs, and organisms. The highly coordinated cell differentiation and proliferation events illustrate the importance of cell-cell communication during growth and development. In Arabidopsis thaliana, ERECTA (ER), a receptor-like protein kinase, plays important roles in promoting localized cell proliferation, which determines inflorescence architecture, organ shape, and size. However, the downstream signaling components remain unidentified. Here, we report a mitogen-activated protein kinase (MAPK; or MPK) cascade that functions downstream of ER in regulating localized cell proliferation. Similar to an er mutant, loss of function of MPK3/MPK6 or their upstream MAPK kinases (MAPKKs; or MKKs), MKK4/MKK5, resulted in shortened pedicels and clustered inflorescences. Epistasis analysis demonstrated that the gain of function of MKK4 and MKK5 transgenes could rescue the loss-of-function er mutant phenotype at both morphological and cellular levels, suggesting that the MPK3/MPK6 cascade functions downstream of the ER receptor. Furthermore, YODA (YDA), a MAPKK kinase, was shown to be upstream of MKK4/MKK5 and downstream of ER in regulating inflorescence architecture based on both gain- and loss-of-function data. Taken together, these results suggest that the YDA-MKK4/MKK5-MPK3/MPK6 cascade functions downstream of the ER receptor in regulating localized cell proliferation, which further shapes the morphology of plant organs.

The status and development of treatment techniques of typical waste electrical and electronic equipment in China: a review.

A large quantity of waste electrical and electronic equipment (WEEE) is being generated because technical innovation promotes the unceasing renewal of products. China's household appliances and electronic products have entered the peak of obsolescence. Due to lack of technology and equipment, recycling of WEEE is causing serious environment pollution. In order to achieve the harmless disposal and resource utilization of WEEE, researchers have performed large quantities of work, and some demonstration projects have been built recently. In this paper, the treatment techniques of typical WEEE components, including printed circuit boards, refrigerator cabinets, toner cartridges, cathode ray tubes, liquid crystal display panels, batteries (Ni-Cd and Li-ion), hard disk drives, and wires are reviewed. An integrated recycling system with environmentally friendly and highly efficient techniques for processing WEEE is proposed. The orientation of further development for WEEE recycling is also proposed.

Phosphorylation of CAX transporters controls Ca2+ homeostasis.

Plants rely on a sophisticated innate immune system to recognize and defend against invading pathogens. The first line of plant innate immunity called pattern-triggered immunity (PTI) is initiated upon detection of pathogen-associated molecular patterns (PAMPs) by plasma membrane-localized pattern recognition receptors (PRRs) (Jones and Dangl, 2006). A well-characterized PRR is the Arabidopsis receptor-like kinase (RLK) FLS2, which complexes with the co-receptor BAK1 to detect the bacterial PAMP flagellin (or its major epitope flg22) (Zipfel, 2014). Downstream of PAMP-triggered PRR activation, the receptor-like cytoplasmic kinases (RLCKs), such as BIK1 and RIPK, associate with and are activated by PRRs to trigger diverse downstream immune signaling events, including reactive oxygen species (ROS) burst, phosphatidic acid (PA) production, increase of cytoplasmic calcium ([Ca2+]cyt) concentration, and activation of mitogen-activated protein kinase (MAPK) cascades, which collectively lead to the establishment of plant PTI (Bigeard et al., 2015).