@article{ding_levin_2007, title={The interventionary state in China and programs and curricula at a Chinese vocational university}, volume={53}, ISSN={["1573-174X"]}, DOI={10.1007/s10734-005-7836-4}, number={5}, journal={HIGHER EDUCATION}, author={Ding, Anning and Levin, John S.}, year={2007}, month={May}, pages={539–560} }
 @article{levin_thompson_csinos_stephenson_weissinger_2005, title={Matrix attachment regions increase the efficiency and stability of RNA-mediated resistance to Tomato Spotted Wilt Virus in transgenic tobacco}, volume={14}, ISSN={["1573-9368"]}, DOI={10.1007/s11248-004-5413-8}, abstractNote={Matrix attachment regions (MARs) are DNA elements that can increase and stabilize transgene expression. We investigated the effect of the RB7 MAR on transgenic virus resistance. Constructs for resistance to tomato spotted wilt virus (TSWV) with and without flanking RB7 MARs were used to transform tobacco and produce homozygous lines. The population with the MAR construct had a significantly higher percentage of TSWV resistant plants in the R1 generation than the nonMAR population. Each resistant line was advanced to the R4 generation, and significantly fewer MAR lines lost resistance over generations compared to the nonMAR population. Lines with TSWV resistance in growth chamber tests were also resistant in field trials. Two lines that were resistant in the R1 generation and susceptible in the R4 were examined in more detail in order to determine if transcriptional silencing of the transgene was occurring in the later generation. Short interfering 21-25 nt RNAs from the transgene that are characteristic of post-transcriptional gene silencing (PTGS) were present in the resistant R1 plants, but not the susceptible R4 plants, indicating that virus resistance was associated with PTGS of the transgene. Loss of resistance was accompanied by an increase in promoter methylation in both lines. In line M41, the transgene was fully silenced at the transcriptional level in the R4 as shown by nuclear run-on assays. In line NM13, transgene transcription and RNA accumulation was still present in the R4 generation, but the level of transcription was not sufficient to trigger PTGS, suggesting that this line may have partial transcriptional silencing. These results are consistent with the concept that MARs may prevent transcriptional silencing.}, number={2}, journal={TRANSGENIC RESEARCH}, author={Levin, JS and Thompson, WF and Csinos, AS and Stephenson, MG and Weissinger, AK}, year={2005}, month={Apr}, pages={193–206} }
 @article{lewis_milla_levin_2005, title={Molecular and genetic characterization of N. glutinosa L. chromosome segments in tobacco mosaic virus (TMV)-resistant tobacco accessions}, volume={45}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2005.0121}, abstractNote={Tobacco mosaic virus (TMV)‐resistant flue‐cured tobacco (Nicotiana tabacum L.) cultivars have been developed using the N gene derived from N. glutinosa L. Their adoption has been low, however, because of unfavorable linkage drag effects. Strategies to overcome this problem might include pursuit of alternative introgression events and/or use of molecular markers for selection against deleterious alien chromatin. Previous workers demonstrated the presence of a TMV‐resistance mechanism on more than one chromosome of the tobacco genome. The objectives of this research were to determine the relative genomic positions of TMV resistance loci in a set of 12 TMV‐resistant tobacco accessions and to use amplified fragment length polymorphism (AFLP) markers for characterization of this material with respect to linked alien chromatin. Five accessions were found to carry a TMV resistance gene on chromosome H. Seven accessions were found to carry a resistance factor on an alternative chromosome. Polymerase chain reaction results indicated that the N gene from N. glutinosa is responsible for resistance in all 12 accessions. A set of 168 AFLP markers specific to the N. glutinosa donor chromosome was identified and used to reveal variability among the 12 accessions for the relative amounts of N. glutinosa chromatin linked to the N gene. The relative propensity for crossing over within the alien segment when in different genomic positions was evaluated in BC1F1 families derived from three different accessions. Lines possessing the N gene on chromosome H may be of greater practical value because of relatively smaller introgressed alien segments and increased potential for obtaining crossover events within the segments.}, number={6}, journal={Crop Science}, publisher={Crop Science Society of America}, author={Lewis, R.S. and Milla, S.R. and Levin, J.S.}, year={2005}, pages={2355–2362} }
 @article{milla_levin_lewis_rufty_2005, title={RAPD and SCAR markers linked to an introgressed gene conditioning resistance to Peronospora tabacina D.B. Adam in tobacco}, volume={45}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2004.0754}, abstractNote={Blue mold, caused by the fungal pathogen Peronospora tabacina D.B. Adam, is one of the most important foliar diseases of tobacco (Nicotiana tabacum L.). Identification of molecular markers linked to genetic factors controlling resistance would facilitate development of resistant cultivars. Bulked segregant analysis was used to screen 1216 random amplified polymorphic DNA (RAPD) primers for their ability to reveal polymorphism between DNA bulks from susceptible doubled haploid (DH) lines and resistant DH lines possessing resistance derived from cultivar Ovens 62. Fifteen RAPD markers were tentatively identified as being linked to a major gene conditioning resistance to blue mold. These 15 markers (12 in coupling phase linkage with resistance and three in repulsion phase) were found to lie within a single linkage group of 36.6 cM and were subsequently tested on 122 DH lines derived from crosses between resistant and susceptible parents. F tests revealed statistically significant associations between resistance and each of the 15 RAPD markers. Interval mapping was used to more accurately place the quantitative trait locus (QTL) controlling resistance on the linkage map. The RAPD markers were screened on a set of 45 resistant and susceptible cultivars or breeding lines and four Nicotiana species. At variance with previous reports, marker genotypes indicated that resistance in Ovens 62 and most other blue mold resistant lines likely originated from N. debneyi Domin. Two RAPD markers flanking the most likely QTL position were converted to sequence characterized amplified region (SCAR) markers. These markers should aid in development of blue mold‐resistant tobacco cultivars worldwide.}, number={6}, journal={Crop Science}, publisher={Crop Science Society of America}, author={Milla, S.R. and Levin, J.S. and Lewis, R.S. and Rufty, R.C.}, year={2005}, pages={2346–2354} }
 @article{liu_levin_murray_wernsman_weissinger_2003, title={A multi-generation analysis of the stability of transgenic virus resistance in doubled-haploid tobacco lines}, volume={12}, number={2}, journal={Molecular Breeding}, author={Liu, Y. S. and Levin, J. S. and Murray, J. S. and Wernsman, E. A. and Weissinger, A. K.}, year={2003}, pages={145–156} }