Sexual reproduction: Is the genetic pathway for female germ cell specification conserved in land plants?

Land plants share several core factors responsible for female gametophyte development, despite their differing structures and developmental programs. New work providing molecular dissection of reproductive phases in non-angiosperm plants is a powerful tool for elucidating the underlying genetic network.

Frequency of laughter and work engagement among Japanese employees: a cross-sectional study during COVID-19.

Laughter is associated with better health and occurs most frequently during casual conversations. However, the COVID-19 pandemic has impaired social interactions, which may have reduced the frequency of laughter and led to poor well-being among workers. This study investigated the relationship between laughter frequency and work engagement among Japanese employees during the pandemic. We conducted a web-based survey among Japanese employees (20-59 yr) via an internet survey company in December 2021; 1,058 valid data were analysed. Of the respondents, 65.1% laughed at least once a week, but the frequency was much lower than that reported in previous studies conducted before the pandemic. Additionally, those who laughed at least once a week had significantly higher work engagement scores than those who laughed less than once a month. Although employees reduced their frequency of laughter during the pandemic, a certain frequency of laughter may be important for maintaining their work engagement.

Job demands and temporomandibular disorders: mediating and moderating effects of psychological distress and recovery experiences.

OBJECTIVES: This study examined the relationship between recovery experience, job demands, psychological distress, and temporomandibular disorders (TMD) in Japanese workers. METHODS: It used cross-sectional data from the fourth survey of a multi-wave longitudinal project, conducted using the registered monitors of an internet research company. Finally, 1278 respondents' data were analyzed (655 males, 623 females; mean [SD] age = 41.63 [10.31] years). We utilized Sugiaski's TMD screening question to assess TMD prevalence, Brief Job Stress Questionnaire to assess job demands, Kessler Psychological Distress Scale (K6) to assess psychological distress, and the Japanese version of the Recovery Experience Questionnaire to assess recovery experiences. The moderated mediation analysis was conducted using the Process macro program for SPSS developed by Preacher and Hayes, examining the effect of job demands on TMD through psychological distress, moderated by the recovery experience. RESULTS: The results showed that 13.1% (n = 168) of the respondents had TMD. Mediation analysis indicated high job demands were associated with an increased TMD prevalence through psychological distress. The moderated mediation analysis revealed that relaxation and control moderated the relationship between job demands and psychological distress. CONCLUSIONS: This cross-sectional study established the relationship between job demands, psychological distress, and TMD among Japanese workers. The findings suggest that increased job demands contribute to high TMD prevalence through the mediation of psychological distress, moderated by relaxation and control.

Boredom and engagement at work: do they have different antecedents and consequences?

This study aimed to demonstrate the empirical distinctiveness of boredom at work and work engagement in relation to their potential antecedents (job demands and job resources) and consequences (psychological distress and turnover intention) based on the Job Demands-Resources model. A three-wave longitudinal survey was conducted among registered monitors of an Internet survey company in Japan. The questionnaire included scales for boredom at work, work engagement, psychological distress, and turnover intention as well as participants' job characteristics and demographic variables. The hypothesized model was evaluated via structural equation modeling with 1,019 participants who were employed full-time. As expected, boredom at work was negatively associated with quantitative job demands and job resources and positively associated with psychological distress and turnover intention. In contrast, work engagement was positively associated with job resources and negatively associated with turnover intention. Thus, boredom at work and work engagement had different potential antecedents and were inversely related to employee well-being and organizational outcomes. However, contrary to expectations, qualitative job demands were not significantly associated with boredom at work. Further investigation is needed to understand the relationship between boredom and qualitative job demands, which require sustained cognitive load and the use of higher skills.

Protocol: an improved method for inducing sporophyte generation in the model moss Physcomitrium patens under nitrogen starvation.

BACKGROUND: Land plants exhibit a haplodiplontic life cycle, whereby multicellular bodies develop in both the haploid and diploid generations. The early-diverging land plants, known as bryophytes, have a haploid-dominant life cycle, in which a short-lived multicellular body in the diploid generation, known as the sporophyte, develops on the maternal haploid gametophyte tissues. The moss Physcomitrium (Physcomitrella) patens has become one of the most powerful model systems in evolutionary plant developmental studies. To induce diploid sporophytes of P. patens, several protocols are implemented. One of the conventional approaches is to grow approximately one-month-old gametophores for another month on Jiffy-7 pellets made from the peat moss that is difficult to fully sterilize. A more efficient method to obtain all tissues throughout the life cycle should accelerate studies of P. patens. RESULTS: Here, we investigated the effect of nitrogen conditions on the growth and development of P. patens. We provide an improved protocol for the sporophyte induction of P. patens using a BCD-based solid culture medium without Jiffy-7 pellets, based on the finding that the formation of gametangia and subsequent sporophytes is promoted by nitrogen-free growth conditions. The protocol consists of two steps; first, culture the protonemata and gametophores on nitrogen-rich medium under continuous light at 25 °C, and then transfer the gametophores onto nitrogen-free medium under short-day and at 15 °C for sporophyte induction. The protocol enables to shorten the induction period and reduce the culture space. CONCLUSIONS: Our more efficient and shortened protocol for inducing the formation of sporophytes will contribute to future studies into the fertilization or the diploid sporophyte generation of P. patens.

Association of Work-Related Sedentary Behavior With Mental Health and Work Engagement Among Japanese White- and Blue-Collar Workers.

OBJECTIVE: This study investigated the association of work-related sedentary behavior with mental health and work engagement among white- and blue-collar workers. METHODS: An Internet survey was conducted among 1600 workers aged 20 to 59 years. A total of 1213 valid responses were analyzed to examine the association of work-related sedentary behavior with mental health and work engagement. RESULTS: Higher level of occupational sedentary behavior significantly associated with poorer mental health and lower work engagement among white-collar workers. Considering the effect of occupation, association of sedentary behavior with mental health disappeared, whereas association with work engagement remained for white-collar workers. CONCLUSIONS: Our result suggested the importance of decreasing work-related sedentary behavior for enhancing work engagement regardless of the occupation for white-collar workers. Further study is needed to confirm the association between these variables for blue-collar workers.

What can hornworts teach us?

The hornworts are a small group of land plants, consisting of only 11 families and approximately 220 species. Despite their small size as a group, their phylogenetic position and unique biology are of great importance. Hornworts, together with mosses and liverworts, form the monophyletic group of bryophytes that is sister to all other land plants (Tracheophytes). It is only recently that hornworts became amenable to experimental investigation with the establishment of Anthoceros agrestis as a model system. In this perspective, we summarize the recent advances in the development of A. agrestis as an experimental system and compare it with other plant model systems. We also discuss how A. agrestis can help to further research in comparative developmental studies across land plants and to solve key questions of plant biology associated with the colonization of the terrestrial environment. Finally, we explore the significance of A. agrestis in crop improvement and synthetic biology applications in general.

Associations between Stigma, Cognitive Appraisals, Coping Strategies and Stress Responses among Japanese Women Undergoing Infertility Treatment.

The number of infertility treatment cycles in Japan is the highest worldwide. Studies have shown that stigma is a predictor of stress-related symptoms including anxiety and depression in women undergoing infertility treatment. Stress management to prevent stress-related symptoms may be crucial; however, few studies have examined the model of stigma and stress responses. Based on the stress-coping model, we hypothesized that stigma threatens the identity of such women and that coping failure increases stress responses. We aimed to explore the role of cognitive appraisals and coping strategies as mediators of the association between the stigma of infertility and stress responses. In December 2021, we conducted a cross-sectional study in Japan, in which 254 women undergoing infertility treatment completed a web-based survey. Hierarchical multiple regression analysis was conducted to analyze the associations between stigma, cognitive appraisals, coping strategies, and stress responses. The results showed that explanatory power increased with each additional variable in the following order: stigma, cognitive appraisals, and coping. Participants with a high level of stigma evaluated it as threatening, and used self-blame and venting coping strategies, and showed higher stress responses. Conversely, participants who used positive reframing coping strategies exhibited lower stress responses. Based on this, effective strategies to address stigma and stress responses are necessitated.

An ancestral function of strigolactones as symbiotic rhizosphere signals.

In flowering plants, strigolactones (SLs) have dual functions as hormones that regulate growth and development, and as rhizosphere signaling molecules that induce symbiosis with arbuscular mycorrhizal (AM) fungi. Here, we report the identification of bryosymbiol (BSB), an SL from the bryophyte Marchantia paleacea. BSB is also found in vascular plants, indicating its origin in the common ancestor of land plants. BSB synthesis is enhanced at AM symbiosis permissive conditions and BSB deficient mutants are impaired in AM symbiosis. In contrast, the absence of BSB synthesis has little effect on the growth and gene expression. We show that the introduction of the SL receptor of Arabidopsis renders M. paleacea cells BSB-responsive. These results suggest that BSB is not perceived by M. paleacea cells due to the lack of cognate SL receptors. We propose that SLs originated as AM symbiosis-inducing rhizosphere signaling molecules and were later recruited as plant hormone.

Association between Stigma and Anxiety, Depression, and Psychological Distress among Japanese Women Undergoing Infertility Treatment.

Japan has the highest number of cases of infertility treatment in the world. Studies have indicated that women undergoing infertility treatment feel stigmatized and suffer from psychological symptoms such as anxiety and depression. However, in Japan, few studies have quantitatively examined the association between the stigma of infertility and psychological symptoms, and, to our knowledge, no study has examined its association using a scale with tested reliability and validity. This study aims to quantitatively examine the relationship between infertility stigma and anxiety, depression, and psychological distress among women undergoing infertility treatment, using a scale that has been validated for reliability and validity. The cross-sectional study was conducted in December 2021 through a web-based survey of 254 participants undergoing infertility treatment. A multiple regression analysis was performed to examine the relationship between stigma and anxiety, depression, and psychological distress. Stigma was a statistically significant predictor of anxiety, depression, and psychological distress (standardized ß = 0.58, p < 0.001; ß = 0.50, p < 0.001; ß = 0.62, p < 0.001, respectively) after controlling for sociodemographic and infertility characteristics. Future studies should examine the causal relationship between stigma and anxiety, depression, and psychological distress and how to intervene to reduce stigma among women undergoing infertility treatment.

Phylogenetic distribution and expression pattern analyses identified a divergent basal body assembly protein involved in land plant spermatogenesis.

Land plant spermatozoids commonly possess characteristic structures such as the spline, which consists of a microtubule array, the multilayered structure (MLS) in which the uppermost layer is a continuum of the spline, and multiple flagella. However, the molecular mechanisms underpinning spermatogenesis remain to be elucidated. We successfully identified candidate genes involved in spermatogenesis, deeply divergent BLD10s, by computational analyses combining multiple methods and omics data. We then examined the functions of BLD10s in the liverwort Marchantia polymorpha and the moss Physcomitrium patens. MpBLD10 and PpBLD10 are required for normal basal body (BB) and flagella formation. Mpbld10 mutants exhibited defects in remodeling of the cytoplasm and nucleus during spermatozoid formation, and thus MpBLD10 should be involved in chromatin reorganization and elimination of the cytoplasm during spermiogenesis. We identified orthologs of MpBLD10 and PpBLD10 in diverse Streptophyta and found that MpBLD10 and PpBLD10 are orthologous to BLD10/CEP135 family proteins, which function in BB assembly. However, BLD10s evolved especially quickly in land plants and MpBLD10 might have acquired additional functions in spermatozoid formation through rapid molecular evolution.

Development of the Japanese Version of the Infertility Stigma Scale: Examination of Its Reliability and Validity.

The stigma of infertility negatively affects health, resulting in mental distress and poor quality of life. An appropriate scale is essential to examine the stigma experienced by infertile women and provide adequate interventions. Therefore, we developed a Japanese version of the Infertility Stigma Scale (ISS). After examining the content validity of this scale, we conducted an online survey of women undergoing fertility treatment to test the scale's structural validity, internal consistency, intra-rater reliability, known-groups validity, convergent validity, and discriminant validity. A total of 254 participants were included in the analysis. The results of confirmatory factor analysis of four factors based on the original scale revealed the optimal fit. Cronbach's alpha was 0.95 for the total score. Concerning test−retest analysis, the total score of the ISS and subscale had a high Spearman correlation coefficient (ρ = 0.61−0.88, p < 0.001). For convergent validity, the association between the ISS and social support, self-esteem, and family functioning was significantly negatively correlated. The results of the multitrait scaling analysis scale showed that correlations of all items exceeded 0.40, and scaling errors (7/81, 8.6%) were few. The Japanese version of the ISS was confirmed to have acceptable reliability and validity.

The complete plastid genome sequence of the enigmatic moss, Takakia lepidozioides (Takakiopsida, Bryophyta): evolutionary perspectives on the largest collection of genes in mosses and the intensive RNA editing.

KEY MESSAGE: Complete chloroplast genome sequence of a moss, Takakia lepidozioides (Takakiopsida) is reported. The largest collection of genes in mosses and the intensive RNA editing were discussed from evolutionary perspectives. We assembled the entire plastid genome sequence of Takakia lepidozioides (Takakiopsida), emerging from the first phylogenetic split among extant mosses. The genome sequences were assembled into a circular molecule 149,016 bp in length, with a quadripartite structure comprising a large and a small single-copy region separated by inverted repeats. It contained 88 genes coding for proteins, 32 for tRNA, four for rRNA, two open reading frames, and at least one pseudogene (tufA). This is the largest number of genes of all sequenced plastid genomes in mosses and Takakia is the only moss that retains the seven coding genes ccsA, cysA, cysT, petN rpoA, rps16 and trnPGGG. Parsimonious interpretation of gene loss suggests that the last common ancestor of bryophytes had all seven genes and that mosses lost at least three of them during their diversification. Analyses of the plastid transcriptome identified the extraordinary frequency of RNA editing with more than 1100 sites. We indicated a close correlation between the monoplastidy of vegetative tissue and the intensive RNA editing sites in the plastid genome in land plant lineages. Here, we proposed a hypothesis that the small population size of plastids in each vegetative cell of some early diverging land plants, including Takakia, might cause the frequent fixation of mutations in plastid genome through the intracellular genetic drift and that deleterious mutations might be continuously compensated by RNA editing during or following transcription.

An Agrobacterium-mediated stable transformation technique for the hornwort model Anthoceros agrestis.

Despite their key phylogenetic position and their unique biology, hornworts have been widely overlooked. Until recently there was no hornwort model species amenable to systematic experimental investigation. Anthoceros agrestis has been proposed as the model species to study hornwort biology. We have developed an Agrobacterium-mediated method for the stable transformation of A. agrestis, a hornwort model species for which a genetic manipulation technique was not yet available. High transformation efficiency was achieved by using thallus tissue grown under low light conditions. We generated a total of 274 transgenic A. agrestis lines expressing the ß-glucuronidase (GUS), cyan, green, and yellow fluorescent proteins under control of the CaMV 35S promoter and several endogenous promoters. Nuclear and plasma membrane localization with multiple color fluorescent proteins was also confirmed. The transformation technique described here should pave the way for detailed molecular and genetic studies of hornwort biology, providing much needed insight into the molecular mechanisms underlying symbiosis, carbon-concentrating mechanism, RNA editing and land plant evolution in general.

Seed-coat protective neolignans are produced by the dirigent protein AtDP1 and the laccase AtLAC5 in Arabidopsis.

Lignans/neolignans are generally synthesized from coniferyl alcohol (CA) in the cinnamate/monolignol pathway by oxidation to generate the corresponding radicals with subsequent stereoselective dimerization aided by dirigent proteins (DIRs). Genes encoding oxidases and DIRs for neolignan biosynthesis have not been identified previously. In Arabidopsis thaliana, the DIR AtDP1/AtDIR12 plays an essential role in the 8-O-4' coupling in neolignan biosynthesis by unequivocal structural determination of the compound missing in the atdp1 mutant as a sinapoylcholine (SC)-conjugated neolignan, erythro-3-{4-[2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-hydroxymethylethoxy]-3,5-dimethoxyphenyl}acryloylcholine. Phylogenetic analyses showed that AtDP1/AtDIR12 belongs to the DIR-a subfamily composed of DIRs for 8-8' coupling of monolignol radicals. AtDP1/AtDIR12 is specifically expressed in outer integument 1 cells in developing seeds. As a putative oxidase for neolignan biosynthesis, we focused on AtLAC5, a laccase gene coexpressed with AtDP1/AtDIR12. In lac5 mutants, the abundance of feruloylcholine (FC)-conjugated neolignans decreased to a level comparable to those in the atdp1 mutant. In addition, SC/FC-conjugated neolignans were missing in the seeds of mutants defective in SCT/SCPL19, an enzyme that synthesizes SC. These results strongly suggest that AtDP1/AtDIR12 and AtLAC5 are involved in neolignan biosynthesis via SC/FC. A tetrazolium penetration assay showed that seed coat permeability increased in atdp1 mutants, suggesting a protective role of neolignans in A. thaliana seeds.

The hornworts: morphology, evolution and development.

Extant land plants consist of two deeply divergent groups, tracheophytes and bryophytes, which shared a common ancestor some 500 million years ago. While information about vascular plants and the two of the three lineages of bryophytes, the mosses and liverworts, is steadily accumulating, the biology of hornworts remains poorly explored. Yet, as the sister group to liverworts and mosses, hornworts are critical in understanding the evolution of key land plant traits. Until recently, there was no hornwort model species amenable to systematic experimental investigation, which hampered detailed insight into the molecular biology and genetics of this unique group of land plants. The emerging hornwort model species, Anthoceros agrestis, is instrumental in our efforts to better understand not only hornwort biology but also fundamental questions of land plant evolution. To this end, here we provide an overview of hornwort biology and current research on the model plant A. agrestis to highlight its potential in answering key questions of land plant biology and evolution.

Validation of the Japanese Version of the Burnout Assessment Tool.

The current study aimed to validate the Japanese version of the Burnout Assessment Tool (BAT-J), a new burnout measure. We conducted an Internet survey to confirm the validity and reliability of the BAT-J, using registered monitors from a Japanese survey company. The first-wave survey was conducted in May 2018, with 1,032 monitors. Of these, 498 participated in the second-wave survey in June 2018 to confirm 1-month test-retest reliability. We examined the factorial validity of the BAT-J core symptoms (BAT-JC) and BAT-J secondary symptoms (BAT-JS), as well as their reliability (internal consistency and test-retest reliability) and construct validity. Factorial validity was examined using confirmatory factor analyses and exploratory structural equation modeling bifactor analyses. Convergent and discriminant validity were examined using multitrait-multimethod frameworks well as the average variance explained. Exploratory structural equation modeling bifactor solutions for the BAT-JC, BAT-JS, and BAT-J demonstrated the best fit to the data. They also indicated that the general factor accounted for over two-thirds of the common variance explained. Internal consistency and test-retest reliability were confirmed. Convergent and internal discriminant validity of the BAT-JC were confirmed vis-ȧ-vis burnout, as assessed with the Maslach Burnout Inventory - General Survey. Moreover, external discriminant validity of the BAT-J was demonstrated for work engagement and workaholism. Finally, both BAT scales showed significant positive relationships with job demands and turnover intention. All validity results were in line with the job demands-resources model. The results of the current study provide the first evidence for the BAT-J's reliability and factorial and construct validity.

Detection of Asian-Type Borrelia miyamotoi from Ixodes ricinus Inhabiting Tver Province (Russia): A Sympatric Region for I. ricinus and Ixodes persulcatus.

Borrelia miyamotoi, a hard tick-borne relapsing fever agent, was sampled in Ixodes ricinus and Ixodes persulcatus ticks from the Tver province in Russia (a sympatric region of both tick species) and examined by TaqMan-PCR targeting the 16S rRNA gene. Borrelia was detected in 4 out of 168 ticks: 2 out of 58 I. ricinus ticks (infection rate 2.9%) and 2 out of 110 I. persulcatus ticks (1.8%). The agent was identified as B. miyamotoi on the basis of the 16S and 23S rDNA intergenic spacer and glycerophosphodiester phosphodiesterase gene sequencing analyses. Interestingly, the genes sequences detected from one I. ricinus tick were identical to those of Asian-type B. miyamotoi from I. persulcatus. This tick was identified as I. ricinus by sequencing analysis of internal transcribed spacer 2 and mitochondrial cytochrome oxidase subunit 1. The results suggest that the I. ricinus ticks were infected with Asian-type B. miyamotoi in a sympatric region for I. ricinus and I. persulcatus.

Anthoceros genomes illuminate the origin of land plants and the unique biology of hornworts.

Hornworts comprise a bryophyte lineage that diverged from other extant land plants >400 million years ago and bears unique biological features, including a distinct sporophyte architecture, cyanobacterial symbiosis and a pyrenoid-based carbon-concentrating mechanism (CCM). Here, we provide three high-quality genomes of Anthoceros hornworts. Phylogenomic analyses place hornworts as a sister clade to liverworts plus mosses with high support. The Anthoceros genomes lack repeat-dense centromeres as well as whole-genome duplication, and contain a limited transcription factor repertoire. Several genes involved in angiosperm meristem and stomatal function are conserved in Anthoceros and upregulated during sporophyte development, suggesting possible homologies at the genetic level. We identified candidate genes involved in cyanobacterial symbiosis and found that LCIB, a Chlamydomonas CCM gene, is present in hornworts but absent in other plant lineages, implying a possible conserved role in CCM function. We anticipate that these hornwort genomes will serve as essential references for future hornwort research and comparative studies across land plants.

A conserved strategy of chalcone isomerase-like protein to rectify promiscuous chalcone synthase specificity.

Land plants produce diverse flavonoids for growth, survival, and reproduction. Chalcone synthase is the first committed enzyme of the flavonoid biosynthetic pathway and catalyzes the production of 2',4,4',6'-tetrahydroxychalcone (THC). However, it also produces other polyketides, including p-coumaroyltriacetic acid lactone (CTAL), because of the derailment of the chalcone-producing pathway. This promiscuity of CHS catalysis adversely affects the efficiency of flavonoid biosynthesis, although it is also believed to have led to the evolution of stilbene synthase and p-coumaroyltriacetic acid synthase. In this study, we establish that chalcone isomerase-like proteins (CHILs), which are encoded by genes that are ubiquitous in land plant genomes, bind to CHS to enhance THC production and decrease CTAL formation, thereby rectifying the promiscuous CHS catalysis. This CHIL function has been confirmed in diverse land plant species, and represents a conserved strategy facilitating the efficient influx of substrates from the phenylpropanoid pathway to the flavonoid pathway.