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1.
Behav Sci (Basel) ; 14(3)2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38540550

ABSTRACT

Constructive play is a creative process-oriented activity that promotes children's engaged learning through building and designing with materials. This study investigated a parent-implemented intervention to promote active engagement in constructive play for preschool-aged children at risk for developmental delay. This study utilized a single-subject multiple-baseline across-participants design with four participants. Visual analysis of the data identified a functional relation between the temporal, physical, and social-emotional environmental support provided by the parents and the children's active engagement in constructive play. Parents reported the intervention as meaningful to their lives, indicating strong social validity. These findings highlight the importance of centering and working with parents in their home environment and provide evidence that empowering parents to provide support and minimize barriers facilitates children's active engagement in constructive play.

2.
Phytopathology ; 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38451704

ABSTRACT

HC-Pro and CP genes of a potyvirus facilitate cell-to-cell movement and are involved in the systemic movement of the viruses. The interaction between HC-Pro and CP is mandatory for aphid transmission. Two turnip mosaic virus (TuMV) isolates, RC4 and YC5, were collected from calla lily plants in Taiwan. The virus derived from the infectious clone pYC5 cannot move systemically in Chenopodium quinoa plants and lacks aphid transmissibility in Nicotiana benthamiana plants, like the initially isolated virus. Sequence analysis revealed that two amino acids P5 and A206, of YC5 CP uniquely differ from RC4 and other TuMV strains. Recombination assay and site-directed mutagenesis revealed that the fifth residue of leucine (L) at the N-terminal region of CP (TuMV-RC4), instead of proline (P) (TuMV-YC5), is critical to permit the systemic spread in C. quinoa plants. Moreover, the single substitution mutant YC5-CPP5L became aphid transmissible similar to RC4. Fluorescence microscopy revealed that YC5-GFP was restricted in the petioles of inoculated leaves, while YC5-CPP5L-GFP translocated through the petioles of inoculated leaves, main stem, and the petioles of upper uninoculated leaves of C. quinoa plants. In addition, YC5-GUS was blocked at the basal part of the petiole connecting to the main stem of the inoculated C. quinoa plants, while YC5-CPP5L-GFP translocated to the upper leaves. Thus, a single amino acid, the residue L5 at the N-terminal region right before the 6DAG8 motif, is critical for the systemic translocation ability of TuMV in a local-lesion host and for aphid transmissibility in a systemic host.

3.
Article in English | MEDLINE | ID: mdl-35954939

ABSTRACT

This study aimed to further the understanding of transactional relationships that exist between problem behaviors and academic performance in early childhood. Early academic and behavior difficulties increase the risk of school disengagement, academic failure, and dropout. Although children's academic and behavioral difficulties have been shown to be intercorrelated, little research has focused on how the relationship reciprocates and progresses in early childhood. This study investigated how problem behaviors (i.e., externalizing and internalizing) influence and are influenced by academic performance (i.e., poor reading and math) from kindergarten to third grade. Participants included 18,135 students (51.22% boys) derived from a nationally representative sample in the Early Childhood Longitudinal Study, Kindergarten Class of 2011 (ECLS-K: 2011). Teacher ratings of children's internalizing (low self-esteem, anxiety, loneliness, or sadness) and externalizing (fighting, arguing, showing anger, impulsively acting, and disruptive behaviors) problem behaviors, as well as direct assessments of children's academic performance (reading and math), were collected yearly. Cross-lagged panel modeling (CLPM) was employed to examine reciprocal relationships between problem behaviors and academic performance over time from kindergarten to third grade. The results supported the transactional relationships in early childhood, with higher externalizing as well as internalizing problem behaviors predicting lower academic performance and lower academic performance predicting higher externalizing and internalizing problem behaviors. The implications for research, prevention, and early intervention regarding the progression of academic and behavioral problems are discussed.


Subject(s)
Academic Performance , Problem Behavior , Child , Child Behavior , Child, Preschool , Female , Humans , Longitudinal Studies , Male , Schools
4.
Mol Plant Pathol ; 23(7): 947-965, 2022 07.
Article in English | MEDLINE | ID: mdl-35285990

ABSTRACT

Control of plant viruses by cross-protection is limited by the availability of effective protective strains. Incorporation of an NIa-protease processing site in the extreme N-terminal region of the helper component protease (HC-Pro) of turnip mosaic virus (TuMV) resulted in a mutant virus TuHND I that induced highly attenuated symptoms. Recombination analysis verified that two variations, F7I mutation and amino acid 7-upstream-deletion, in HC-Pro co-determined TuHND I attenuation. TuHND I provided complete protection to Nicotiana benthamiana and Brassica campestris subsp. chinensis plants against infection by the severe parental strain. Aphid transmission tests revealed that TuHND I was not aphid-transmissible. An RNA silencing suppression (RSS) assay by agroinfiltration suggested the RSS-defective nature of the mutant HC-Pro. In the context (amino acids 3-17) encompassing the two variations of HC-Pro, we uncovered an FWKG-α-helix 1 (αH1) element that influenced the functions of aphid transmission and RSS, whose motifs were located far downstream. We further demonstrated that HC-Pro F7 was a critical residue on αH1 for HC-Pro functions and that reinstating αH1 in the RSS-defective HC-Pro of TuHND I restored the protein's RSS function. Yeast two-hybrid and bimolecular fluorescence complementation assays indicated the FWKG-αH1 element as an integral part of the HC-Pro self-interaction domain. The possibility of regulation of the mechanistically independent functions of RSS and aphid transmission by the FWKG-αH1 element is discussed. Extension of TuMV HC-Pro FWKG-αH1 variations to another potyvirus, zucchini yellow mosaic virus, also generated nonaphid-transmissible cross-protective mutant viruses. Hence, the modification of the FWKG-αH1 element can generate effective attenuated viruses for the control of potyviruses by cross-protection.


Subject(s)
Aphids , Potyvirus , Animals , Cysteine Endopeptidases/genetics , Cysteine Endopeptidases/metabolism , Plant Diseases/prevention & control , Potyvirus/physiology , Viral Proteins
5.
Disabil Health J ; 15(3): 101269, 2022 07.
Article in English | MEDLINE | ID: mdl-35131214

ABSTRACT

BACKGROUND: Children born of low birth weight (LBW) and/or premature may have developmental delays and difficulties. The vulnerability, without early intervention, would have detrimental lifelong effects. OBJECTIVES: This study examined 1) the relationship between LBW and prematurity and the occurrence and timing of children's receipt of developmental and special education services; and 2) whether poverty intersects with LBW and prematurity affecting service receipt. METHODS: This population-based study used cross-sectional data from the National Survey of Children's Health which consisted of approximately 52,000 participants aged 1-17 between 2017 and 2018 in the United States. We conducted logistic regression to analyze the predictive relationship of LBW/prematurity and the occurrence of receiving developmental and special education services. We then conducted ordered logistic regression to examine whether LBW and prematurity predicted the timing of receiving developmental and special education services. Further, we conducted moderating analyses to examine whether the predictive relationships above varied with poverty. The analyses listed above were weighted to reflect the population drawn. RESULTS: Children born with LBW and prematurity were more likely to receive developmental and special education services and they tended to receive services earlier than those born at normal weight and term. Educational disparities were evident among children in low-income families. Children of LBW in low-income families were less likely to receive earlier services than those in affluent families. CONCLUSIONS: This study indicates developmental and special education needs of children born LBW and/or premature. With restrained assets, low-income families may need more assistance to promote optimal development for their children.


Subject(s)
Disabled Persons , Child , Cross-Sectional Studies , Education, Special , Humans , Infant, Low Birth Weight , Infant, Newborn , Poverty , United States
6.
J Youth Adolesc ; 46(11): 2273-2288, 2017 11.
Article in English | MEDLINE | ID: mdl-28508249

ABSTRACT

Patterns of adjustment for youth victimized by peers vary depending on whether youth are identified as victims through self-reports, peer-reports, or both. In order to provide more targeted strategies that may help mitigate negative consequences associated with specific victimization groups, more information is needed about how these youth perceive their school ecology (bullying and academic ecology), their feelings of school belonging, and their valuing of school. Based on the convergence of self- and peer-reports of victimization, we identified four victim groups from a sample of students in 5th grade classrooms (N = 1360; 52.8% girls, 53.1% White, 34.6% Black or Hispanic, 12.2% Native American, Asian, or other) using Latent Profile Analysis (LPA): convergent victims (high self- and peer-reports), self-identified victims (high self-, low peer-reports), peer-identified victims (low self-, high peer-reports), and nonvictims (low self- and peer-reports). Convergent victims' perceptions were similar to nonvictims with key differences being convergent victims' greater willingness to protect peers being bullied but lower feelings of school belonging compared to nonvictims. Peer-identified and self-identified victims perceived differences in the bullying and academic ecology including peer-identified victims' greater willingness to protect peers and expectations for more peers to encourage bulling against them compared to self-identified victims. However, both peer- and self-identified victims perceived greater emotional risk of participating in class and had lower feelings of school belonging compared to nonvictims. Implications for supporting youth with divergent self- and peer-reported victimization status as they transition to middle school are discussed.


Subject(s)
Bullying , Crime Victims/psychology , Peer Group , Students/psychology , Animals , Cattle , Child , Emotions , Female , Humans , Interpersonal Relations , Longitudinal Studies , Male , Perception , Schools , Self Report , Social Environment , United States
7.
Aggress Behav ; 43(3): 263-272, 2017 May.
Article in English | MEDLINE | ID: mdl-27779315

ABSTRACT

This study examined the associations between teacher attunement to aggressive students and students' characteristics in a sample (n = 278) of youth in 5th-grade classrooms with the assumption that certain student characteristics may either prime or hinder teachers' attunement to aggressive students. Teacher attunement was measured as the agreement between teacher- and peer-nominations for students who start fights. Teachers rated their students on the following characteristics: academic competence, affiliation, popularity, internalizing behavior, and Olympian qualities. Higher affiliation, popularity, and internalizing behavior were associated with decreased odds for teacher attunement to aggressive youth. Higher Olympian qualities were associated with increased odds for teacher attunement to aggressive youth. Implications for interventions are discussed. Aggr. Behav. 43:263-272, 2017. © 2016 Wiley Periodicals, Inc.


Subject(s)
Aggression/psychology , Child Behavior/psychology , Peer Group , School Teachers/psychology , Social Perception , Students/psychology , Child , Female , Humans , Male
8.
Kidney Blood Press Res ; 41(3): 267-77, 2016.
Article in English | MEDLINE | ID: mdl-27160740

ABSTRACT

BACKGROUND/AIMS: Lipopolysaccharides (LPS) binding to Toll-like receptor 4 (TLR4) activate NADPH oxidase gp91 subunit-mediated inflammation and oxidative damage. Recognizing the high binding affinity of sialic acid (SA) with LPS, we further explored the preventive potential of SA pretreatment on LPS-evoked acute renal failure (ARF). METHODS: We determined the effect of intravenous SA 30 min before LPS-induced injury in urethane-anesthetized female Wistar rats by evaluating kidney reactive oxygen species (ROS) responses, renal and systemic hemodynamics, renal function, histopathology, and molecular mechanisms. RESULTS: LPS time-dependently reduced arterial blood pressure, renal microcirculation, and increased blood urea nitrogen and creatinine in the rats. LPS enhanced monocyte/macrophage infiltration and ROS production, and subsequently impaired kidneys with the enhancement of TLR4/NADPH oxidase gp91/Caspase 3/poly-(ADP-ribose)-polymerase (PARP)-mediated apoptosis in the kidneys. SA pretreatment effectively alleviated LPS-induced ARF. The levels of LPS-increased ED-1 infiltration and ROS production in the kidney were significantly depressed by SA pretreatment. Furthermore, SA pretreatment significantly depressed TLR4 activation, gp91 expression, and Caspase 3/PARP induced apoptosis in the kidneys. CONCLUSION: We suggest that pretreatment of SA significantly and preventively attenuated LPS-induced detrimental effects on systemic and renal hemodynamics, renal ROS production and renal function, as well as, LPS-activated TLR4/gp91/Caspase3 mediated apoptosis signaling.


Subject(s)
Acute Kidney Injury/prevention & control , Apoptosis/drug effects , Lipopolysaccharides/pharmacology , N-Acetylneuraminic Acid/pharmacology , Acute Kidney Injury/metabolism , Acute Kidney Injury/pathology , Animals , Female , Kidney/physiopathology , Membrane Glycoproteins/physiology , NADPH Oxidase 2 , NADPH Oxidases/physiology , Rats , Rats, Wistar , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Toll-Like Receptor 4/physiology
9.
Mol Plant Microbe Interact ; 27(9): 944-55, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24804808

ABSTRACT

Cross-protection triggered by a mild strain of virus acts as a prophylaxis to prevent subsequent infections by related viruses in plants; however, the underling mechanisms are not fully understood. Through mutagenesis, we isolated a mutant strain of Turnip mosaic virus (TuMV), named Tu-GK, that contains an Arg182Lys substitution in helper component-proteinase (HC-Pro(K)) that confers complete cross-protection against infection by a severe strain of TuMV in Nicotiana benthamiana, Arabidopsis thaliana Col-0, and the Arabidopsis dcl2-4/dcl4-1 double mutant defective in DICER-like ribonuclease (DCL)2/DCL4-mediated silencing. Our analyses showed that HC-Pro(K) loses the ability to interfere with microRNA pathways, although it retains a partial capability for RNA silencing suppression triggered by DCL. We further showed that Tu-GK infection triggers strong salicylic acid (SA)-dependent and SA-independent innate immunity responses. Our data suggest that DCL2/4-dependent and -independent RNA silencing pathways are involved, and may crosstalk with basal innate immunity pathways, in host defense and in cross-protection.


Subject(s)
Arabidopsis Proteins/genetics , Cell Cycle Proteins/genetics , Cross Protection , Cysteine Endopeptidases/genetics , Plant Diseases/immunology , Potyvirus/genetics , Ribonuclease III/genetics , Viral Proteins/genetics , Amino Acid Motifs , Amino Acid Substitution , Arabidopsis/immunology , Arabidopsis/virology , Arabidopsis Proteins/metabolism , Cell Cycle Proteins/metabolism , Cysteine Endopeptidases/metabolism , Gene Expression Regulation, Plant , High-Throughput Nucleotide Sequencing , MicroRNAs/genetics , Models, Biological , Mutation , Plant Diseases/virology , Plant Leaves/immunology , Plant Leaves/virology , Plants, Genetically Modified , Potyvirus/physiology , RNA Interference , Ribonuclease III/metabolism , Salicylic Acid/metabolism , Seedlings/immunology , Seedlings/virology , Sequence Analysis, RNA , Nicotiana/immunology , Nicotiana/virology , Viral Proteins/metabolism
10.
NeuroRehabilitation ; 34(2): 365-72, 2014.
Article in English | MEDLINE | ID: mdl-24419015

ABSTRACT

BACKGROUND: Despite of a growing body of research on vocational and educational difficulties for students with traumatic brain injury (TBI), only limited empirical studies specifically examined how school transition services facilitate later employment outcomes. OBJECTIVE: This exploratory, prospective longitudinal study examined the prevalence of employment and characteristics of transition planning practices that promoted positive school-to-work transition for students with TBI. METHOD: The participants (n = 200) was drawn from the National Longitudinal Transition Study-2 (NLTS-2), a ten-year study which followed a large nationally representative sample of youth with disabilities through secondary education in into young adulthood. Logistic regression was used to investigate the associations between student, school, and collaborative engagement in the planning process and employment outcomes up to 8 years after high school. RESULTS: Among youth with TBI, 51% held current employment at the time of interview and 73% had been employed at any time after high school. Findings showed that students with TBI who had transition goals for postsecondary education were more likely to be employed at some point since leaving high school. The findings also support active student engagement and leadership in the transition planning process, and the inclusion of outside organizations and individuals. CONCLUSIONS: Findings indicate the impact of student, school and adult service agency engagement in transition planning processes. Implications for educational practices and future research are discussed.


Subject(s)
Brain Injuries/rehabilitation , Disabled Persons/rehabilitation , Employment/statistics & numerical data , Rehabilitation, Vocational/methods , Students , Adolescent , Adult , Disabled Persons/statistics & numerical data , Female , Humans , Longitudinal Studies , Male , Prospective Studies , Young Adult
11.
Clin J Pain ; 30(6): 536-43, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24135902

ABSTRACT

OBJECTIVES: The main aim of the study was to generate initial convergent validity evidence for the Pain and Discomfort Scale (PADS) for use with nonverbal adults with intellectual disabilities. MATERIALS AND METHODS: Forty-four adults with intellectual disability (mean age=46, 52% male) were evaluated using a standardized sham-controlled and blinded sensory testing protocol, from which Facial Action Coding System (FACS) and PADS scores were tested for (1) sensitivity to an array of calibrated sensory stimuli; (2) specificity (active vs. sham trials); and (3) concordance. RESULTS: The primary findings were those participants who were reliably coded using both FACS and PADS approaches as being reactive to the sensory stimuli (FACS: F(2,86)=4.71, P<0.05, PADS: F(2,86)=21.49, P<0.05) (sensitivity evidence), not reactive during the sham stimulus trials (FACS: F(1,43)=3.77, P=0.06, PADS: F(1,43)=5.87, P=0.02) (specificity evidence), and there were significant (r=0.41 to 0.51, P<0.01) correlations between PADS and FACS (convergent validity evidence). DISCUSSION: FACS is an objective coding platform for facial expression. It requires intensive training and resources for scoring. As such it may be limited for clinical application. PADS was designed for clinical application. PADS scores were comparable with FACS scores under controlled evaluation conditions providing partial convergent validity evidence for its use.


Subject(s)
Facial Expression , Intellectual Disability/physiopathology , Pain Measurement/methods , Pain/diagnosis , Pain/physiopathology , Female , Humans , Male , Middle Aged , Motor Activity , Physical Stimulation , Reproducibility of Results , Sensitivity and Specificity
12.
Dev Psychopathol ; 25(2): 501-15, 2013 May.
Article in English | MEDLINE | ID: mdl-23627959

ABSTRACT

School mobility has been shown to increase the risk of poor achievement, behavior problems, grade retention, and high school dropout. Using data over 25 years from the Chicago Longitudinal Study, we investigated the unique risk of school moves on a variety of young adult outcomes including educational attainment, occupational prestige, depression symptoms, and criminal arrests. We also investigated how the timing of school mobility, whether earlier or later in the academic career, may differentially predict these outcomes over and above associated risks. Results indicate that students who experience more school changes between kindergarten and 12th grade are less likely to complete high school on time, complete fewer years of school, attain lower levels of occupational prestige, experience more symptoms of depression, and are more likely to be arrested as adults. Furthermore, the number of school moves predicted outcomes above and beyond associated risks such as residential mobility and family poverty. When timing of school mobility was examined, results indicated more negative outcomes associated with moves later in the grade school career, particularly between 4th and 8th grades.


Subject(s)
Achievement , Employment , Students/psychology , Adolescent , Adult , Chicago , Child , Depression/psychology , Female , Humans , Longitudinal Studies , Male , Risk Factors , Schools
13.
J Sch Psychol ; 50(5): 559-79, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23040755

ABSTRACT

In light of persistent Black-White achievement gaps for boys, this study examined publicly monitored risks believed to be associated with being behind academically for an entire subpopulation of African American boys in a large urban public school district. Also examined were indicators of academic engagement hypothesized to mediate the relations between risks and low achievement. Findings indicated that the Black-White achievement gap for boys was matched by a comparable difference in risk experiences. Multilevel linear regression models controlling for poverty found that both the type and accumulation of risk experiences explained a significant amount of variation in reading and mathematics achievement for the subpopulation of African American boys. Socio-familial risks were related to the poorest academic outcomes. Academic engagement indicators significantly mediated relations between risks and achievement. Implications of this research for collective school and community actions to make race, gender, and place matter in educational public policy were discussed.


Subject(s)
Black or African American/education , Educational Status , Adolescent , Black or African American/statistics & numerical data , Child , Community Participation , Educational Measurement , Female , Humans , Male , Philadelphia/epidemiology , Racial Groups/education , Racial Groups/statistics & numerical data , Resilience, Psychological , Risk Factors , Underachievement , Urban Population
14.
Early Educ Dev ; 22(4): 574-592, 2011.
Article in English | MEDLINE | ID: mdl-37609433

ABSTRACT

Research Findings: In early childhood education, the social ecology of the child is considered critical for healthy behavioral development. There is, however, relatively little information based on directly observing what children do that describes the moment-by-moment (i.e., sequential) relation between physical aggression and peer rejection acts in early childhood contexts. Such information could be useful for policy and practice because it may inform specific intervention targets. In this descriptive study, a real-time direct observation protocol was used to measure the frequency of physically aggressive acts and peer rejection acts. The sequential association between directly observed physical aggression and peer rejection acts was examined for 5 high-risk preschool children (Child Behavior Checklist/Teacher Report Form clinical scores) at the beginning (Time 1 [T1]) and end (Time 2 [T2]) of their preschool year. Descriptive analyses showed that both aggression and peer rejection acts increased over the course of the preschool year. Sequential analyses showed that there was a significant (p < .05) increase in the likelihood of physical aggression followed by peer rejection acts from T1 to T2 as indexed by Yule's Q (a transformed odds ratio that controls for differences in the frequencies of children's target behavior). Similarly, there was a significant (p < .05) increase in the likelihood of peer rejection acts followed by physical aggression from T1 to T2. Practice or Policy: Considering the long-term adversity that aggression and related early conduct problems can introduce into the education and social service system, additional studies using direct observation to study early social dynamics between peer rejection acts and physical aggression in at-risk children seem warranted to improve experts' ability to disrupt this developmental trajectory and improve peer relationships.

16.
Child Youth Serv Rev ; 32(8): 1108-1120, 2010 Aug.
Article in English | MEDLINE | ID: mdl-27867242

ABSTRACT

Identification of the early determinants of substance abuse is a major focus of life course research. In this study, we investigated the child, family, and school-related antecedents of the onset and prevalence of substance abuse by age 26 for a cohort of 1,208 low-income minority children in the Chicago Longitudinal Study. Data onon well-being have been collected prospectively since birth from administrative records, parents, teachers, and children. Results indicated that the prevalence of substance abuse by age 26 was 32 percent (self reports or criminal justice system records) with a median age of first use of 17. Probit regression analysis indicated that substance abuse prevalence was primarily determined by gender (males had a higher rate), trouble making behavior by age 12, school mobility, and previous substance use. Family and peer predictors included involvement in the child welfare system by age 9, parent expectations for school success at age 9, parent substance abuse by children's age 15, and deviant peer affiliation by age 16. Age of first substance use was predicted by gender and race/ethnicity (males and Blacks had earlier incidence), involvement in the child welfare system, and family risk status at age 8. As with prevalence, the pattern of predictors for males was similar to the overall sample but the magnitude of effects was stronger.. The predictors of the timing of substance use dependency were gender, family conflict by age 5, involvement in the child welfare system, social maturity at age 9, adolescent school mobility, and school dropout by age 16. Findings indicate that the promotion of family involvement and positive school and social behavior can reduce the risk of substance abuse.

17.
PLoS Pathog ; 5(2): e1000312, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19247440

ABSTRACT

Plant microRNAs (miRNA) guide cleavage of target mRNAs by DICER-like proteins, thereby reducing mRNA abundance. Native precursor miRNAs can be redesigned to target RNAs of interest, and one application of such artificial microRNA (amiRNA) technology is to generate plants resistant to pathogenic viruses. Transgenic Arabidopsis plants expressing amiRNAs designed to target the genome of two unrelated viruses were resistant, in a highly specific manner, to the appropriate virus. Here, we pursued two different goals. First, we confirmed that the 21-nt target site of viral RNAs is both necessary and sufficient for resistance. Second, we studied the evolutionary stability of amiRNA-mediated resistance against a genetically plastic RNA virus, TuMV. To dissociate selective pressures acting upon protein function from those acting at the RNA level, we constructed a chimeric TuMV harboring a 21-nt, amiRNA target site in a non-essential region. In the first set of experiments designed to assess the likelihood of resistance breakdown, we explored the effect of single nucleotide mutation within the target 21-nt on the ability of mutant viruses to successfully infect amiRNA-expressing plants. We found non-equivalency of the target nucleotides, which can be divided into three categories depending on their impact in virus pathogenicity. In the second set of experiments, we investigated the evolution of the virus mutants in amiRNA-expressing plants. The most common outcome was the deletion of the target. However, when the 21-nt target was retained, viruses accumulated additional substitutions on it, further reducing the binding/cleavage ability of the amiRNA. The pattern of substitutions within the viral target was largely dominated by G to A and C to U transitions.


Subject(s)
Evolution, Molecular , MicroRNAs/genetics , Mosaic Viruses , Nicotiana/genetics , Plants, Genetically Modified/genetics , Base Sequence , Bayes Theorem , Chi-Square Distribution , Immunity, Innate/genetics , MicroRNAs/immunology , Molecular Sequence Data , Mosaic Viruses/genetics , Mosaic Viruses/physiology , Mutation , Plant Diseases/genetics , Plants, Genetically Modified/immunology , Sequence Analysis, DNA , Nicotiana/immunology , Tymovirus/genetics , Tymovirus/physiology
18.
Virus Res ; 130(1-2): 210-27, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17689817

ABSTRACT

The N-terminal (NT) regions of particular protein-coding sequences are generally used for in-frame insertion of heterologous open reading frames (ORFs) in potyviral vectors for protein expression in plants. An infectious cDNA clone of Turnip mosaic virus (TuMV) isolate YC5 was engineered at the generally used NT regions of HC-Pro and CP, and other possibly permissive sites to investigate their effectiveness to express the GFP (jellyfish green fluorescent protein) and Der p 5 (allergen from the dust mite, Dermatophagoides pteronyssinus) ORFs. The results demonstrated the permissiveness of the NT regions of P3, CIP and NIb to carry the ORFs and express the translates as part of the viral polyprotein, the processing of which released free-form proteins in the host cell milieu. However, these sites varied in their permissiveness to retain the ORFs intact and hence affect the heterologous protein expression. Moreover, strong influence of the inserted ORF and host plants in determining the permissiveness of a viral genomic context to stably carry the alien ORFs and hence to support their prolonged expression was also noticed. In general, the engineered sites were relatively more permissive to the GFP ORF than to the Der p 5 ORF. Among the hosts, the local lesion host, Chenopodium quinoa Willd. showed the highest extent of support to TuMV to stably carry the heterologous ORFs at the engineered sites and the protein expression therefrom. Among the systemic hosts, Nicotiana benthamiana Domin proved more supportive to TuMV to carry and express the heterologous ORFs than the Brassica hosts, whereas the protein expression levels were significantly higher and more stable in the plants of Brassica campestris L. var. chinensis and B. campestris L. var. ching-geeng than those in the plants of B. juncea L. and B. campestris L. var. pekinensis.


Subject(s)
Plants, Genetically Modified/metabolism , Potyvirus/genetics , Recombinant Proteins/biosynthesis , Antigens, Dermatophagoides/biosynthesis , Antigens, Dermatophagoides/genetics , Arthropod Proteins , Brassica/metabolism , Brassica/virology , Chenopodium quinoa/metabolism , Chenopodium quinoa/virology , Genetic Vectors , Green Fluorescent Proteins/biosynthesis , Green Fluorescent Proteins/genetics , Plants, Genetically Modified/genetics , Plants, Genetically Modified/virology , Polyproteins/genetics , Recombinant Proteins/genetics , Nicotiana/metabolism , Nicotiana/virology , Viral Proteins/genetics
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