RESUMEN
BACKGROUND: Melaleuca quinquenervia (broad-leaved paperbark) is a coastal wetland tree species that serves as a foundation species in eastern Australia, Indonesia, Papua New Guinea, and New Caledonia. While extensively cultivated for its ornamental value, it has also become invasive in regions like Florida, USA. Long-lived trees face diverse pest and pathogen pressures, and plant stress responses rely on immune receptors encoded by the nucleotide-binding leucine-rich repeat (NLR) gene family. However, the comprehensive annotation of NLR encoding genes has been challenging due to their clustering arrangement on chromosomes and highly repetitive domain structure; expansion of the NLR gene family is driven largely by tandem duplication. Additionally, the allelic diversity of the NLR gene family remains largely unexplored in outcrossing tree species, as many genomes are presented in their haploid, collapsed state. RESULTS: We assembled a chromosome-level pseudo-phased genome for M. quinquenervia and described the allelic diversity of plant NLRs using the novel FindPlantNLRs pipeline. Analysis reveals variation in the number of NLR genes on each haplotype, distinct clustering patterns, and differences in the types and numbers of novel integrated domains. CONCLUSIONS: The high-quality M. quinquenervia genome assembly establishes a new framework for functional and evolutionary studies of this significant tree species. Our findings suggest that maintaining allelic diversity within the NLR gene family is crucial for enabling responses to environmental stress, particularly in long-lived plants.
RESUMEN
BACKGROUND: Anxiety disorders are common in youth and cause significant distress and impairment to the individual and family. Oxytocin (OT), a nine amino acid peptide, is implicated in anxiety regulation and modulation of close interpersonal and attachment behavior. Anxiety disorders have been linked to low levels of salivary OT in youth. Research has also linked oxytocinergic functioning to social support, warm contact, and bonding, and indicated that contact with attachment figures stimulates OT response. We examined OT response to a brief, positive youth-mother interaction in clinically anxious youth. We investigated whether quality of the youth-mother interaction as well as the presence of particular anxiety disorders, are associated with youth OT response. METHOD: Salivary OT from 41 youth with primary DSM-5 anxiety disorders was assayed before and after a 7-min youth-mother interaction that was later systematically coded by two reliable coders. Youth and mothers also completed rating scales of youth anxiety symptoms. RESULTS: Affective touch, maternal sensitivity, maternal intrusiveness, youth engagement, and youth initiative all contributed significantly to predicting youth OT response. Repeated measures analyses showed that when affective touch was high youth had greater OT response. OT response was positively associated with the presence of separation anxiety disorder (SAD) and with child ratings of separation anxiety. CONCLUSIONS: The findings highlight the importance of maternal and dyadic behavior patterns to oxytocinergic response in clinically anxious youth, shed light on the association between OT and SAD, and point to possible intervention strategies.
