The mirid bug Apolygus lucorum has become a major agricultural pest since the large-scale cultivation of Bt-cotton. It was assumed that A. lucorum, similarly to other phloem sap insects, could secrete saliva that contains effector proteins into plant interfaces to perturb host cellular processes during feeding. However, the secreted effectors of A. lucorum are still uncharacterized and unstudied. In this study, 1878 putative secreted proteins were identified from the transcriptome of A. lucorum, which either had homology with published aphid effectors or shared common features with plant pathogens and insect effectors. One hundred and seventy-two candidate effectors were used for cell death-inducing/suppressing assays, and a putative salivary gland effector, Apolygus lucorum cell death inhibitor 6 (Al6), was characterized. The mRNAs of Al6 were enriched at feeding stages (nymph and adult) and, in particular, in salivary glands. Moreover, we revealed that the secreted Al6 encoded an active glutathione peroxidase that reduced reactive oxygen species (ROS) accumulation induced by INF1 or Flg22. Expression of the Al6 gene in planta altered insect feeding behavior and promoted plant pathogen infections. Inhibition of cell death and enhanced plant susceptibility to insect and pathogens are dependent on glutathione peroxidase activity of Al6. Thus, this study shows that a candidate salivary gland effector, Al6, functions as a glutathione peroxidase and suppresses ROS induced by pathogen-associated molecular pattern to inhibit pattern-triggered immunity (PTI)-induced cell death. The identification and molecular mechanism analysis of the Al6 candidate effector in A. lucorum will provide new insight into the molecular mechanisms of insect–plant interactions.
Pythium guiyangense
, an oomycete from a genus of mostly plant pathogens, is an effective biological control agent that has wide potential to manage diverse mosquitoes. However, its mosquito-killing mechanisms are almost unknown. In this study, we observed that
P
.
guiyangense
could utilize cuticle penetration and ingestion of mycelia into the digestive system to infect mosquito larvae. To explore pathogenic mechanisms, a high-quality genome sequence with 239 contigs and an N50 contig length of 1,009 kb was generated. The genome assembly is approximately 110 Mb, which is almost twice the size of other sequenced
Pythium
genomes. Further genome analysis suggests that
P
.
guiyangense
may arise from a hybridization of two related but distinct parental species. Phylogenetic analysis demonstrated that
P
.
guiyangense
likely evolved from common ancestors shared with plant pathogens. Comparative genome analysis coupled with transcriptome sequencing data suggested that
P
.
guiyangense
may employ multiple virulence mechanisms to infect mosquitoes, including secreted proteases and kazal-type protease inhibitors. It also shares intracellular Crinkler (CRN) effectors used by plant pathogenic oomycetes to facilitate the colonization of plant hosts. Our experimental evidence demonstrates that CRN effectors of
P
.
guiyangense
can be toxic to insect cells. The infection mechanisms and putative virulence effectors of
P
.
guiyangense
uncovered by this study provide the basis to develop improved mosquito control strategies. These data also provide useful knowledge on host adaptation and evolution of the entomopathogenic lifestyle within the oomycete lineage. A deeper understanding of the biology of
P
.
guiyangense
effectors might also be useful for management of other important agricultural pests.
In recent years, the international social context has become increasingly volatile, uncertain, complex, ambiguous (VUCA), and college students need a high level of long-term occupational engagement to cope with the unpredictability of the current employment environment. In this context, this study used a longitudinal design to explore the relationship between personal growth initiative and occupational engagement among college students and, based on this, further explored the role of vocational identity and Big Five personality traits in it. This study used a questionnaire survey method and the study participants were 700 college students in Shandong, China. And the time interval between the two questionnaire measurements was 4 months, with 559 final valid participants (182 males and 377 females). The following results were found in this study: (1) The cross-lagged model found that personal growth initiative was a significant positive predictor of occupational engagement. (2) The moderated mediation model found that vocational identity mediated the relationship between personal growth initiative and occupational engagement, and that neuroticism among the Big Five personality traits played a moderating role, i.e., individuals with higher level of neuroticism personality trait had a relatively weaker positive predictive effect of vocational identity on occupational engagement. This study concludes that colleges and universities need to understand students’ interests and personality traits and provide more targeted career education (e.g., intentional growth training and cognitive behavioral therapy) to promote their personal growth initiatives, reduce their neuroticism levels and in turn enhance their vocational identity in order to help college students achieve long-term sustainable occupational engagement in the uncertain social context.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.