Cellulose synthesis complexes are homo-oligomeric and hetero-oligomeric in Physcomitrium patens.

The common ancestor of seed plants and mosses contained homo-oligomeric cellulose synthesis complexes (CSCs) composed of identical subunits encoded by a single CELLULOSE SYNTHASE (CESA) gene. Seed plants use different CESA isoforms for primary and secondary cell wall deposition. Both primary and secondary CESAs form hetero-oligomeric CSCs that assemble and function in planta only when all the required isoforms are present. The moss Physcomitrium (Physcomitrella) patens has seven CESA genes that can be grouped into two functionally and phylogenetically distinct classes. Previously, we showed that PpCESA3 and/or PpCESA8 (class A) together with PpCESA6 and/or PpCESA7 (class B) form obligate hetero-oligomeric complexes required for normal secondary cell wall deposition. Here, we show that gametophore morphogenesis requires a member of class A, PpCESA5, and is sustained in the absence of other PpCESA isoforms. PpCESA5 also differs from the other class A PpCESAs as it is able to self-interact and does not co-immunoprecipitate with other PpCESA isoforms. These results are consistent with the hypothesis that homo-oligomeric CSCs containing only PpCESA5 subunits synthesize cellulose required for gametophore morphogenesis. Analysis of mutant phenotypes also revealed that, like secondary cell wall deposition, normal protonemal tip growth requires class B isoforms (PpCESA4 or PpCESA10), along with a class A partner (PpCESA3, PpCESA5, or PpCESA8). Thus, P. patens contains both homo-oligomeric and hetero-oligomeric CSCs.

Perspectives of culturally and linguistically diverse families in the management of children with type 1 diabetes in Western Australia.

OBJECTIVES: Children with Type 1 diabetes (T1D) from different ethnic backgrounds are growing in proportion in clinical practice and tend to have a higher risk of poor health outcomes. The study aimed to investigate the perspectives of culturally and linguistically diverse families in the management of children with T1D in Western Australia. DESIGN: A generic qualitative approach was used. Families of children and adolescents with T1D with first-generation African, Asian or Middle Eastern background were invited to participate in a semi-structured interview. The interviews were audio-recorded, transcribed and analysed thematically. Demographic, clinical and socio-economic data were collected from all participants. RESULTS: Fifteen families (27% African, 33% Middle Eastern, 40% Asian) participated in the study. The mean (SD) age of the child with T1D was 10.2 (5.1) years, had diabetes for 2.9 (1.6) years and an average HbA1c of 67 (15) mmol/mol. Four main themes were identified through qualitative analysis. 'Dietary challenges': lack of adequate food resources posed a barrier to determine carbohydrate amount in traditional meals; 'Linguistic challenges': inadequate reading and language skills affected comprehension of written information and the desire for pictorial resources was reported; 'Limited Support': absence of extended family made management of T1D difficult; and 'Knowledge': a key facilitator, which was acquired through clinic education, enabled families to develop skills to effectively manage T1D. CONCLUSION: The study highlights the need to consider cultural diversity, psychosocial needs, English proficiency and health literacy when assessing and planning diabetes education. These findings will be useful to formulate a more culturally sensitive approach to diabetes education to improve care and outcomes for young people with T1D from culturally and linguistically diverse families.

Exploring the lived experiences of women with children during COVID-19: Maternal stress and coping mechanisms.

This paper presents the results of a qualitative study of mothers' lived experiences during the COVID-19 lockdown in the United States. An analysis of open-ended interviews with 44 mothers who had children ages zero-to-five identified two main themes: (1) increased stress among mothers; and (2) resilience through the use of coping mechanisms. The findings indicate that the COVID-19 pandemic has led to higher stress among mothers due to issues of work-family life balance, family and children's needs, decision-making about getting sick, concerns for children's development, and lack of clarity from government officials. Mothers described using a variety of problem-focused and emotion-focused methods to cope with this stress. The lived experiences of mothers during the pandemic highlights the need for innovations in childcare modalities, paid leave policies to relieve stress, and strengthening whole family processes and resilience through the use of coping mechanisms.

Hybrid closed-loop therapy with a first-generation system increases confidence and independence in diabetes management in youth with type 1 diabetes.

AIM: Hybrid closed-loop (HCL) therapy improves glycaemic control in adolescents with type 1 diabetes; however, little is known about their lived experience using these systems. The aim of this study was to explore the lived experiences of youth with type 1 diabetes using HCL therapy, and their parents, to provide insight into their lived experiences. METHODS: Adolescents and young adults aged 12-25 years, who used Medtronic MiniMed™ 670G HCL system during a 6-month randomised clinical trial, and their parents, were invited to participate in a semi-structured interview at the end of the study. Open-ended questions were used to explore the lived experiences of families using HCL. The interviews were audio-recorded, transcribed and analysed using thematic analysis to determine the main themes. RESULTS: In all, 17 young people with type 1 diabetes mean ± SD age: 17.5 ± 4.2 years, diabetes duration: 11.0 ± 4.9 years and HbA1c 64 ± 9 mmol/mol (8.0 ± 0.8%) and 10 parents were interviewed. Three themes were identified: (1) 'Developing confidence and trust in the system', (2) 'Reduction in anxiety' and (3) 'Issues with device'. They reported a positive experience using HCL, with improvements in glucose levels and increased independence with diabetes management. However, frustration around the number of alarms and notifications associated with the system were also identified as issues. CONCLUSION: Both youth and parents acknowledged the benefits of this first-generation HCL system in improving glycaemic outcomes and in providing flexibility and independence. These lived experiences provide valuable information in the introduction and provision of targeted education with HCL therapy.

A referral pathway for stoma patients.

Alison Roberts, Nurse Team Leader, Respond Healthcare (alison.roberts@respond.co.uk) was a runner-up in the Stoma Nurse of the Year category of the British Journal of Nursing Awards 2021.

TERMINAL FLOWER-1/CENTRORADIALIS inhibits tuberisation via protein interaction with the tuberigen activation complex.

Potato tuber formation is a secondary developmental programme by which cells in the subapical stolon region divide and radially expand to further differentiate into starch-accumulating parenchyma. Although some details of the molecular pathway that signals tuberisation are known, important gaps in our knowledge persist. Here, the role of a member of the TERMINAL FLOWER 1/CENTRORADIALIS gene family (termed StCEN) in the negative control of tuberisation is demonstrated for what is thought to be the first time. It is shown that reduced expression of StCEN accelerates tuber formation whereas transgenic lines overexpressing this gene display delayed tuberisation and reduced tuber yield. Protein-protein interaction studies (yeast two-hybrid and bimolecular fluorescence complementation) demonstrate that StCEN binds components of the recently described tuberigen activation complex. Using transient transactivation assays, we show that the StSP6A tuberisation signal is an activation target of the tuberigen activation complex, and that co-expression of StCEN blocks activation of the StSP6A gene by StFD-Like-1. Transcriptomic analysis of transgenic lines misexpressing StCEN identifies early transcriptional events in tuber formation. These results demonstrate that StCEN suppresses tuberisation by directly antagonising the function of StSP6A in stolons, identifying StCEN as a breeding marker to improve tuber initiation and yield through the selection of genotypes with reduced StCEN expression.

Different potato virus Y strains frequently co-localize in single epidermal leaf cells and in the aphid stylet.

Single aphids can simultaneously or sequentially acquire and transmit multiple potato virus Y (PVY) strains. Multiple PVY strains are often found in the same field and occasionally within the same plant, but little is known about how PVY strains interact in plants or in aphid stylets. Immuno-staining and confocal microscopy were used to examine the spatial and temporal dynamics of PVY strain mixtures (PVYO and PVYNTN or PVYO and PVYN) in epidermal leaf cells of 'Samsun NN' tobacco and 'Goldrush' potato. Virus binding and localization was also examined in aphid stylets following acquisition. Both strains systemically infected tobacco and co-localized in cells of all leaves examined; however, the relative amounts of each virus changed over time. Early in the tobacco infection, when mosaic symptoms were observed, PVYO dominated the infection although PVYNTN was detected in some cells. As the infection progressed and vein necrosis developed, PVYNTN was prevalent. Co-localization of PVYO and PVYN was also observed in epidermal cells of potato leaves with most cells infected with both viruses. Furthermore, two strains could be detected binding to the distal end of aphid stylets following virus acquisition from a plant infected with a strain mixture. These data are in contrast with the traditional belief of spatial separation of two closely related potyviruses and suggest apparent non-antagonistic interaction between PVY strains that could help explain the multitude of emerging recombinant PVY strains discovered in potato in recent years.

Functional Characterization of a Glycosyltransferase from the Moss Physcomitrella patens Involved in the Biosynthesis of a Novel Cell Wall Arabinoglucan.

Mixed-linkage (1,3;1,4)-ß-glucan (MLG), an abundant cell wall polysaccharide in the Poaceae, has been detected in ascomycetes, algae, and seedless vascular plants, but not in eudicots. Although MLG has not been reported in bryophytes, a predicted glycosyltransferase from the moss Physcomitrella patens (Pp3c12_24670) is similar to a bona fide ascomycete MLG synthase. We tested whether Pp3c12_24670 encodes an MLG synthase by expressing it in wild tobacco (Nicotiana benthamiana) and testing for release of diagnostic oligosaccharides from the cell walls by either lichenase or (1,4)-ß-glucan endohydrolase. Lichenase, an MLG-specific endohydrolase, showed no activity against cell walls from transformed N. benthamiana, but (1,4)-ß-glucan endohydrolase released oligosaccharides that were distinct from oligosaccharides released from MLG by this enzyme. Further analysis revealed that these oligosaccharides were derived from a novel unbranched, unsubstituted arabinoglucan (AGlc) polysaccharide. We identified sequences similar to the P. patens AGlc synthase from algae, bryophytes, lycophytes, and monilophytes, raising the possibility that other early divergent plants synthesize AGlc. Similarity of P. patens AGlc synthase to MLG synthases from ascomycetes, but not those from Poaceae, suggests that AGlc and MLG have a common evolutionary history that includes loss in seed plants, followed by a more recent independent origin of MLG within the monocots.

Convergent evolution of hetero-oligomeric cellulose synthesis complexes in mosses and seed plants.

In seed plants, cellulose is synthesized by rosette-shaped cellulose synthesis complexes (CSCs) that are obligate hetero-oligomeric, comprising three non-interchangeable cellulose synthase (CESA) isoforms. The moss Physcomitrella patens has rosette CSCs and seven CESAs, but its common ancestor with seed plants had rosette CSCs and a single CESA gene. Therefore, if P. patens CSCs are hetero-oligomeric, then CSCs of this type evolved convergently in mosses and seed plants. Previous gene knockout and promoter swap experiments showed that PpCESAs from class A (PpCESA3 and PpCESA8) and class B (PpCESA6 and PpCESA7) have non-redundant functions in secondary cell wall cellulose deposition in leaf midribs, whereas the two members of each class are redundant. Based on these observations, we proposed the hypothesis that the secondary class A and class B PpCESAs associate to form hetero-oligomeric CSCs. Here we show that transcription of secondary class A PpCESAs is reduced when secondary class B PpCESAs are knocked out and vice versa, as expected for genes encoding isoforms that occupy distinct positions within the same CSC. The class A and class B isoforms co-accumulate in developing gametophores and co-immunoprecipitate, suggesting that they interact to form a complex in planta. Finally, secondary PpCESAs interact with each other, whereas three of four fail to self-interact when expressed in two different heterologous systems. These results are consistent with the hypothesis that obligate hetero-oligomeric CSCs evolved independently in mosses and seed plants and we propose the constructive neutral evolution hypothesis as a plausible explanation for convergent evolution of hetero-oligomeric CSCs.

Potato Mop-Top Virus Co-Opts the Stress Sensor HIPP26 for Long-Distance Movement.

Virus movement proteins facilitate virus entry into the vascular system to initiate systemic infection. The potato mop-top virus (PMTV) movement protein, TGB1, is involved in long-distance movement of both viral ribonucleoprotein complexes and virions. Here, our analysis of TGB1 interactions with host Nicotiana benthamiana proteins revealed an interaction with a member of the heavy metal-associated isoprenylated plant protein family, HIPP26, which acts as a plasma membrane-to-nucleus signal during abiotic stress. We found that knockdown of NbHIPP26 expression inhibited virus long-distance movement but did not affect cell-to-cell movement. Drought and PMTV infection up-regulated NbHIPP26 gene expression, and PMTV infection protected plants from drought. In addition, NbHIPP26 promoter-reporter fusions revealed vascular tissue-specific expression. Mutational and biochemical analyses indicated that NbHIPP26 subcellular localization at the plasma membrane and plasmodesmata was mediated by lipidation (S-acylation and prenylation), as nonlipidated NbHIPP26 was predominantly in the nucleus. Notably, coexpression of NbHIPP26 with TGB1 resulted in a similar nuclear accumulation of NbHIPP26. TGB1 interacted with the carboxyl-terminal CVVM (prenyl) domain of NbHIPP26, and bimolecular fluorescence complementation revealed that the TGB1-HIPP26 complex localized to microtubules and accumulated in the nucleolus, with little signal at the plasma membrane or plasmodesmata. These data support a mechanism where interaction with TGB1 negates or reverses NbHIPP26 lipidation, thus releasing membrane-associated NbHIPP26 and redirecting it via microtubules to the nucleus, thereby activating the drought stress response and facilitating virus long-distance movement.

Functional Specialization of Cellulose Synthase Isoforms in a Moss Shows Parallels with Seed Plants.

The secondary cell walls of tracheary elements and fibers are rich in cellulose microfibrils that are helically oriented and laterally aggregated. Support cells within the leaf midribs of mosses deposit cellulose-rich secondary cell walls, but their biosynthesis and microfibril organization have not been examined. Although the Cellulose Synthase (CESA) gene families of mosses and seed plants diversified independently, CESA knockout analysis in the moss Physcomitrella patens revealed parallels with Arabidopsis (Arabidopsis thaliana) in CESA functional specialization, with roles for both subfunctionalization and neofunctionalization. The similarities include regulatory uncoupling of the CESAs that synthesize primary and secondary cell walls, a requirement for two or more functionally distinct CESA isoforms for secondary cell wall synthesis, interchangeability of some primary and secondary CESAs, and some CESA redundancy. The cellulose-deficient midribs of ppcesa3/8 knockouts provided negative controls for the structural characterization of stereid secondary cell walls in wild type P. patens Sum frequency generation spectra collected from midribs were consistent with cellulose microfibril aggregation, and polarization microscopy revealed helical microfibril orientation only in wild type leaves. Thus, stereid secondary walls are structurally distinct from primary cell walls, and they share structural characteristics with the secondary walls of tracheary elements and fibers. We propose a mechanism for the convergent evolution of secondary walls in which the deposition of aggregated and helically oriented microfibrils is coupled to rapid and highly localized cellulose synthesis enabled by regulatory uncoupling from primary wall synthesis.

Repeated polyploidization of Gossypium genomes and the evolution of spinnable cotton fibres.

Polyploidy often confers emergent properties, such as the higher fibre productivity and quality of tetraploid cottons than diploid cottons bred for the same environments. Here we show that an abrupt five- to sixfold ploidy increase approximately 60 million years (Myr) ago, and allopolyploidy reuniting divergent Gossypium genomes approximately 1-2 Myr ago, conferred about 30-36-fold duplication of ancestral angiosperm (flowering plant) genes in elite cottons (Gossypium hirsutum and Gossypium barbadense), genetic complexity equalled only by Brassica among sequenced angiosperms. Nascent fibre evolution, before allopolyploidy, is elucidated by comparison of spinnable-fibred Gossypium herbaceum A and non-spinnable Gossypium longicalyx F genomes to one another and the outgroup D genome of non-spinnable Gossypium raimondii. The sequence of a G. hirsutum A(t)D(t) (in which 't' indicates tetraploid) cultivar reveals many non-reciprocal DNA exchanges between subgenomes that may have contributed to phenotypic innovation and/or other emergent properties such as ecological adaptation by polyploids. Most DNA-level novelty in G. hirsutum recombines alleles from the D-genome progenitor native to its New World habitat and the Old World A-genome progenitor in which spinnable fibre evolved. Coordinated expression changes in proximal groups of functionally distinct genes, including a nuclear mitochondrial DNA block, may account for clusters of cotton-fibre quantitative trait loci affecting diverse traits. Opportunities abound for dissecting emergent properties of other polyploids, particularly angiosperms, by comparison to diploid progenitors and outgroups.

Management of Early Cervical Stromal Invasion FIGO Stage 1A1 When Margins Are Involved With Cervical Intraepithelial Neoplasia.

OBJECTIVE: Women with International Federation of Gynecology and Obstetrics stage 1A1 cervical carcinoma were evaluated to determine whether repeat excision for large loop excision transformation zone margins positive with cervical intraepithelial neoplasia (CIN) had been undertaken according to the National Health Service Cervical Screening Programme guidelines and if deviations from guidelines adversely affected patient outcome. MATERIALS AND METHODS: We retrospectively studied patients with 1A1 cervical carcinoma treated in our service between May 2010 and July 2015 to determine whether NHSCSP guidelines (May 2010) were followed. This states that if the invasive disease is excised but CIN extends to the excision margin, then a repeat large loop excision transformation zone should be undertaken to exclude further invasive disease and to confirm excision of CIN. RESULTS: Seventeen patients were identified. In one, neither the invasive lesion nor CIN was fully excised. In 5, the lesion and CIN were fully excised. In eleven, the invasive lesion was excised, but CIN was present at a margin. Of these 11 patients, none opted for a repeat excision. All 11 patients had negative cytology at first follow-up (negative up to 4 years [median = 2 years]). CONCLUSIONS: Our outcomes suggest that it may not be necessary to perform a repeat excision for CIN present at the excision margin in women with 1A1 cervical carcinoma when CIN is present either at the endocervical, deep stromal, or ectocervical margin, as long as the invasive focus is fully excised, and patients have been fully counseled and have regular cytology follow-up. This may be an alternative for patients wanting to minimize the risks to fertility posed by repeat excision.

Cellulose synthase 'class specific regions' are intrinsically disordered and functionally undifferentiated.

Cellulose synthases (CESAs) are glycosyltransferases that catalyze formation of cellulose microfibrils in plant cell walls. Seed plant CESA isoforms cluster in six phylogenetic clades, whose non-interchangeable members play distinct roles within cellulose synthesis complexes (CSCs). A 'class specific region' (CSR), with higher sequence similarity within versus between functional CESA classes, has been suggested to contribute to specific activities or interactions of different isoforms. We investigated CESA isoform specificity in the moss, Physcomitrella patens (Hedw.) B. S. G. to gain evolutionary insights into CESA structure/function relationships. Like seed plants, P. patens has oligomeric rosette-type CSCs, but the PpCESAs diverged independently and form a separate CESA clade. We showed that P. patens has two functionally distinct CESAs classes, based on the ability to complement the gametophore-negative phenotype of a ppcesa5 knockout line. Thus, non-interchangeable CESA classes evolved separately in mosses and seed plants. However, testing of chimeric moss CESA genes for complementation demonstrated that functional class-specificity is not determined by the CSR. Sequence analysis and computational modeling showed that the CSR is intrinsically disordered and contains predicted molecular recognition features, consistent with a possible role in CESA oligomerization and explaining the evolution of class-specific sequences without selection for class-specific function.

Associations between social support, psychological well-being, decision making, empowerment, infant and young child feeding, and nutritional status in Ugandan children ages 0 to 24 months.

Maternal capabilities-qualities of mothers that enable them to leverage skills and resources into child health-hold potential influence over mother's adoption of child caring practices, including infant and young child feeding. We developed a survey (n = 195) that assessed the associations of 4 dimensions of maternal capabilities (social support, psychological health, decision making, and empowerment) with mothers' infant and young child feeding practices and children's nutritional status in Uganda. Maternal responses were converted to categorical subscales and an overall index. Scale reliability coefficients were moderate to strong (α range = 0.49 to 0.80). Mothers with higher social support scores were more likely to feed children according to the minimum meal frequency (odds ratio [OR] [95% confidence interval (CI)] = 1.38 [1.10, 1.73]), dietary diversity (OR [95% CI] = 1.56 [1.15, 2.11]), iron rich foods, (OR [95% CI] = 1.47 [1.14, 1.89]), and minimally acceptable diet (OR [95% CI] = 1.55 [1.10, 2.21]) indicators. Empowerment was associated with a greater likelihood of feeding a minimally diverse and acceptable diet. The maternal capabilities index was significantly associated with feeding the minimum number of times per day (OR [95% CI] = 1.29 [1.03, 1.63]), dietary diversity (OR [95% CI] = 1.44 [1.06, 1.94]), and minimally acceptable diet (OR [95% CI] = 1.43 [1.01, 2.01]). Mothers with higher psychological satisfaction were more likely to have a stunted child (OR [95% CI] = 1.31 [1.06, 1.63]). No other associations between the capabilities scales and child growth were significant. Strengthening social support for mothers and expanding overall maternal capabilities hold potential for addressing important underlying determinants of child feeding in the Ugandan context.

The valine and lysine residues in the conserved FxVTxK motif are important for the function of phylogenetically distant plant cellulose synthases.

Cellulose synthases (CESAs) synthesize the ß-1,4-glucan chains that coalesce to form cellulose microfibrils in plant cell walls. In addition to a large cytosolic (catalytic) domain, CESAs have eight predicted transmembrane helices (TMHs). However, analogous to the structure of BcsA, a bacterial CESA, predicted TMH5 in CESA may instead be an interfacial helix. This would place the conserved FxVTxK motif in the plant cell cytosol where it could function as a substrate-gating loop as occurs in BcsA. To define the functional importance of the CESA region containing FxVTxK, we tested five parallel mutations in Arabidopsis thaliana CESA1 and Physcomitrella patens CESA5 in complementation assays of the relevant cesa mutants. In both organisms, the substitution of the valine or lysine residues in FxVTxK severely affected CESA function. In Arabidopsis roots, both changes were correlated with lower cellulose anisotropy, as revealed by Pontamine Fast Scarlet. Analysis of hypocotyl inner cell wall layers by atomic force microscopy showed that two altered versions of Atcesa1 could rescue cell wall phenotypes observed in the mutant background line. Overall, the data show that the FxVTxK motif is functionally important in two phylogenetically distant plant CESAs. The results show that Physcomitrella provides an efficient model for assessing the effects of engineered CESA mutations affecting primary cell wall synthesis and that diverse testing systems can lead to nuanced insights into CESA structure-function relationships. Although CESA membrane topology needs to be experimentally determined, the results support the possibility that the FxVTxK region functions similarly in CESA and BcsA.

Parental Involvement in a School-Based Child Physical Activity and Nutrition Program in Southeastern United States: A Qualitative Analysis of Parenting Capacities.

BACKGROUND: Parent involvement varies widely in school-based programs designed to promote physical activity and healthy nutrition, yet the underlying factors that may limit parent's participation and support of learned behaviors at home are not well understood. METHOD: We conducted a qualitative study that consisted of one focus group (n = 5) and 52 in-depth interviews among parents whose children participated in a school-based physical activity and nutrition (PAN) promotion program in Williamsburg, Virginia, United States. We sought to identify factors that enabled or constrained parent's support of and involvement in children's programs and to understand the underlying factors that contribute to family success in making dietary and physical activity changes at home. RESULTS: Parents identified their physical and mental health, self-confidence, time, and decision making as underlying "capacities" in the family health pattern. When strengthened, these capacities encourage healthful family behavior and support of school-based PAN programs. Families that succeeded in adopting lessons learned from school-based PAN programs identified four primary strategies for success: shared goals, meal planning, modeling of good behaviors, and collective activities. CONCLUSIONS: Interventions that aim to improve child nutrition and physical activity and the broader family health environment should consider underlying capacities of parents and the importance of joint goals and activities.

Factors Associated With Perinatal Hepatitis C Screening Among Exposed Children: 2016-2020.

BACKGROUND AND OBJECTIVES: Children perinatally exposed to hepatitis C virus (HCV) should be screened for infection, yet testing rates are low. Clinical perinatal HCV testing recommendations vary and may contribute to poor completion. This study examines pediatric care factors associated with perinatal HCV testing completion. METHODS: A cohort of people living with HCV in Philadelphia, Pennsylvania, who delivered a live birth in 2016 to 2020 and their children were followed by the Philadelphia Department of Public Health. The association of completion of HCV screening with pregnant/postpartum person demographics, pediatric care factors, and testing policy were retrospectively explored. χ2 and multivariable logistic regressions were used. RESULTS: HCV-positive pregnant people gave birth to 457 children of whom 307 (67.2%) were tested for HCV according to recommendations and 79 (17.2%) were inadequately tested. Children were more likely to be tested if born to a pregnant person with HIV coinfection (P = .007), if they were always on schedule for vaccinations (P < .001), and if they attended the 18-month well visit (P < .001). Completion rates varied significantly by pediatrician's testing policy: 90.9% tested if the policy was for 2 months, 79.6% if 2 to 12 months, 61.9% if 12 months, and 58.5% if 18 months of age (P < .001). CONCLUSIONS: Timing of perinatal HCV testing policies was significantly associated with testing completion rates. Testing at 2 months was associated with far better HCV testing completion than other strategies, regardless of birthing person and pediatrician factors. These findings suggest routine HCV testing of children perinatally exposed to HCV is best achieved in the first year of life.

The role of the potato (Solanum tuberosum) CCD8 gene in stolon and tuber development.

· Strigolactones (SLs) are a class of phytohormones controlling shoot branching. In potato (Solanum tuberosum), tubers develop from underground stolons, diageotropic stems which originate from basal stem nodes. As the degree of stolon branching influences the number and size distribution of tubers, it was considered timely to investigate the effects of SL production on potato development and tuber life cycle. · Transgenic potato plants were generated in which the CAROTENOID CLEAVAGE DIOXYGENASE8 (CCD8) gene, key in the SL biosynthetic pathway, was silenced by RNA interference (RNAi). · The resulting CCD8-RNAi potato plants showed significantly more lateral and main branches than control plants, reduced stolon formation, together with a dwarfing phenotype and a lack of flowering in the most severely affected lines. New tubers were formed from sessile buds of the mother tubers. The apical buds of newly formed transgenic tubers grew out as shoots when exposed to light. In addition, we found that CCD8 transcript levels were rapidly downregulated in tuber buds by the application of sprout-inducing treatments. · These results suggest that SLs could have an effect, solely or in combination with other phytohormones, in the morphology of potato plants and also in controlling stolon development and maintaining tuber dormancy.

The TGB1 movement protein of Potato virus X reorganizes actin and endomembranes into the X-body, a viral replication factory.

Potato virus X (PVX) requires three virally encoded proteins, the triple gene block (TGB), for movement between cells. TGB1 is a multifunctional protein that suppresses host gene silencing and moves from cell to cell through plasmodesmata, while TGB2 and TGB3 are membrane-spanning proteins associated with endoplasmic reticulum-derived granular vesicles. Here, we show that TGB1 organizes the PVX "X-body," a virally induced inclusion structure, by remodeling host actin and endomembranes (endoplasmic reticulum and Golgi). Within the X-body, TGB1 forms helically arranged aggregates surrounded by a reservoir of the recruited host endomembranes. The TGB2/3 proteins reside in granular vesicles within this reservoir, in the same region as nonencapsidated viral RNA, while encapsidated virions accumulate at the outer (cytoplasmic) face of the X-body, which comprises a highly organized virus "factory." TGB1 is both necessary and sufficient to remodel host actin and endomembranes and to recruit TGB2/3 to the X-body, thus emerging as the central orchestrator of the X-body. Our results indicate that the actin/endomembrane-reorganizing properties of TGB1 function to compartmentalize the viral gene products of PVX infection.