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Inflammation in response to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection drives severity of coronavirus disease 2019 (COVID-19) and is influenced by host genetics. To understand mechanisms of inflammation, animal models that reflect genetic diversity and clinical outcomes observed in humans are needed. We report a mouse panel comprising the genetically diverse Collaborative Cross (CC) founder strains crossed to human ACE2 transgenic mice (K18-hACE2) that confers susceptibility to SARS-CoV-2. Infection of CC x K18-hACE2 resulted in a spectrum of survival, viral replication kinetics, and immune profiles. Importantly, in contrast to the K18-hACE2 model, early type I interferon (IFN-I) and regulated proinflammatory responses were required for control of SARS-CoV-2 replication in PWK x K18-hACE2 mice that were highly resistant to disease. Thus, virus dynamics and inflammation observed in COVID-19 can be modeled in diverse mouse strains that provide a genetically tractable platform for understanding anti-coronavirus immunity. Dynamics of type I interferon (IFN) following infection with SARS-CoV-2 are critical in determining disease severity in humans but have been difficult to model in mice. Here, infection of genetically diverse mice reveals how delayed or immediate IFN signaling coordinates antiviral immunity. [ABSTRACT FROM AUTHOR]

In this paper, we define the complex-type k-Padovan numbers and then give the relationships between the 1,k-1\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\left( 1,k-1\right)$$\end{document}-bonacci numbers, the k -Padovan numbers and the complex-type k-Padovan numbers by matrix method. In addition, we study the complex-type k-Padovan sequence modulo m and then we show that for some m the periods of the complex type k-Padovan and k-Padovan sequences modulo m are related. Furthermore, we extend the complex-type k-Padovan sequences to groups. Finally, we obtain the periods of the complex-type 4, 5, 6-Padovan sequences in the semidihedral group SD2m\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$SD_{2^{m}}$$\end{document}, m≥4\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\left( m\ge 4\right)$$\end{document} with respect to the generating pairs x,y\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\left( x,y\right)$$\end{document} and y,x\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\left( y,x\right)$$\end{document}. [ABSTRACT FROM AUTHOR]

Key Message: Genetic analysis identified a unique combination of major QTL for resistance to important soybean nematodes concurrently present in a single soybean accession, which has not been reported earlier. An exotic soybean [Glycine max (L.) Merr.] accession, PI 567305, was reported to be highly resistant to three important nematode species, soybean cyst (SCN), root-knot (RKN), and reniform (RN) nematodes. However, genetic basis controlling broad-spectrum resistance in this germplasm has not been investigated. We report results of genetic analysis to identify genomic loci conferring resistance to these nematode species. A bi-parental population consisting of 242 F8-derived recombinant inbred lines (RILs) was developed from a cross of a nematode susceptible cultivar, Magellan, and resistant accession, PI 567305. The RILs were phenotyped for nematode resistance to three SCN HG types. They were genotyped using the Infinium SoySNP6K BeadChips and genotype-by-sequencing (GBS) methods in an attempt to evaluate the cost-effectiveness and efficiency of these two genotyping platforms. Genetic analysis confirmed the major QTL on chromosomes (Chrs) 10 and 18 with broad-spectrum resistance to the three nematodes present in this germplasm. Haplotype and copy number variation analyses of SCN resistance QTL indicated that PI 567305 has a different haplotype, which is associated with likely a unique SCN resistance mechanism different from Peking- or PI 88788-type resistance. The evaluations of both Infinium Beadchip- and GBS-based genotyping technologies provided comprehensive insights for researchers to choose a cost-effective and efficient platform for QTL mapping and for other genomic studies in soybeans. [ABSTRACT FROM AUTHOR]

Previous studies reported that omega-3 fatty acid and α-linolenic acid are important compounds that prevent cardiovascular disease and cancer in humans. Soybean [ Glycine max (L.) Merr.] oil typically contains ~8 % α-linolenic acid (ALA). Elevated (~15 %) ALA content in seed oil is a trait of wild soybeans ( G. soja Sieb. and Zucc.). Decreasing the ratio of linoleic acid (LA) to ALA to 4:1 or lower (compared to the ratio of 6 or 7:1 found in commercial soybean seed) should have health benefits for humans. This study was conducted to determine the environmental stability of elevated ALA acid recombinant inbred lines (RILs) derived from a cross of PI 483463 (wild soybean with 15 % ALA) and Hutcheson (cultivar with 9 % ALA). The fatty acid profile analysis from nine environments showed that the content of ALA for the RILs 156, 159 and 166 ranged from 10.7 to 15.7, 14.0 to 15.8, and 14.8 to 15.8, and averaged 13.9, 14.9, and 15.2 % respectively. The contents of ALA from these RILs and the wild soybean parent showed consistently higher than cultivated check soybeans. Two of the three RILs with elevated ALA content and ratios of <4:1 LA to ALA were as stable in ALA content as the high and low linolenic acid parents across growing environments. This indicates that lines with elevated ALA content developed from wild soybean PI 483463 are stable in ALA across environments and would be useful in improving soybeans with lower LA to ALA ratios. [ABSTRACT FROM AUTHOR]

Genetic analysis of resistance of plant introduction (PI) 438489B to soybean cyst nematode (SCN) have shown that this PI is highly resistant to many SCN HG types. However, validation of the previously detected quantitative trait loci (QTL) has not been done. In this study, 250 F progeny of a Magellan (susceptible) × PI 438489B (resistant) cross were used for primary genetic mapping to detect putative QTL for resistance to five SCN HG types. QTL confirmation study was subsequently conducted using F recombinant inbred lines (RILs) derived from the same cross. Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were employed for molecular genotyping. Interval mapping (IM), permutation tests, cofactor selection, and composite interval mapping (CIM) were performed to identify and map QTL. Results showed that five QTL intervals were associated with resistance to either multiple- or single-HG types of SCN. Among these, two major QTL for resistance to multiple-SCN HG types were mapped to chromosomes (Chr.) 8 and 18, consistent with the known rhg1 and Rhg4 locations. The other QTL were mapped to Chr. 4. The results of our study confirmed earlier reported SCN resistance QTL in this PI. Moreover, SSR and SNP molecular markers tightly linked to these QTL can be useful for the near-isogenic lines (NILs) development aiming to fine-mapping of these QTL regions and map-based cloning of SCN resistance candidate genes. [ABSTRACT FROM AUTHOR]

Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is the most destructive pest of soybean worldwide. Host plant resistance is an effective approach to control this pest. Plant introduction PI 567516C has been reported to be highly resistant to multiple-HG types of SCN. The objectives of this study were to identify and map novel quantitative trait loci (QTL) for SCN resistance to six HG types (also known as races 1, 2, 3, 5, 14, and LY1). Mapping was conducted using 250 F progeny derived from a Magellan (susceptible) × PI 567516C (resistant) cross. F recombinant inbred lines (RILs) developed from the F progeny were employed to confirm the putative QTL identified. A total of 927 polymorphic simple sequence repeats (SSR) and single nucleotide polymorphism (SNP) markers were genotyped. Following the genetic linkage analysis, permutation tests and composite interval mapping were performed to identify and map QTL. Four QTL were associated with resistance to either multiple- or single-SCN HG types. Two QTL for resistance to multiple-SCN HG types were mapped to Chromosomes 10 and 18 and have not been reported in other SCN resistance sources. New QTL were confirmed by analysis of 250 F RILs from the same population. SSR and SNP markers closely associated with these QTL can be useful for the development of near-isogenic lines for fine-mapping and positional cloning of candidate genes for SCN resistance. [ABSTRACT FROM AUTHOR]

Soybean cyst nematode (SCN) is a major soybean pest throughout the soybean growing regions in the world, including the USA. Soybean PI 90763 is an important SCN resistance source. It is resistant to several SCN populations including races 2, 3 and 5. But its genetics of resistance is not well known. The objectives of this study were to: (1) confirm quantitative trait loci (QTLs) for resistance to SCN race 3 in PI 90763 and (2) identify QTLs for resistance to SCN races 2 and 5. QTLs were searched in Hamilton × PI 90763 F2:3populations using 193 polymorphic simple sequence repeats (SSRs) covering 20 linkage groups (LGs). QTLs for resistance to SCN were identified on LGs A2, B1, E, G, J and L. The same QTL was suggested for resistance to different SCN races where their 1-LOD support intervals of QTL positions highly overlapped. The QTL on LG G was associated with resistance to races 2, 3 and 5. The QTL on LG B1 was associated with resistance to races 2 and 5. The QTL on LG J was associated with resistance to races 2 and 3. The QTLs on LGs A2 and L were associated with resistance to race 3. The QTL on LG E was associated with resistance to race 5. We conclude that LGs A2 and B1 may represent an important distinction between resistance to SCN race 3 and resistance to SCN races 2 and 5 in soybean. [ABSTRACT FROM AUTHOR]

Soil water-logging can cause severe damage to soybean [ Glycine max (L.) Merr.] and results in significant yield reduction. The objective of this study was to identify quantitative trait loci (QTL) that condition water-logging tolerance (WLT) in soybean. Two populations with 103 and 67 F6:11 recombinant inbred lines (RILs) from A5403 × Archer (Population 1) and P9641 × Archer (Population 2), respectively, were used as the mapping populations. The populations were evaluated for WLT in manually flooded fields in 2001, 2002, and 2003. Significant variation was observed for WLT among the lines in the two populations. No transgressive tolerant segregants were observed in either population. Broad-sense heritability of WLT for populations 1 and 2 were 0.59 and 0.43, respectively. The tolerant and sensitive RILs from each population were selected to create a tolerant bulk and a sensitive bulk, respectively. The two bulks and the parents of each population were tested with 912 simple sequence repeat (SSR) markers to select candidate regions on the linkage map that were associated with WLT. Markers from the candidate regions were used to genotype the RILs in both populations. Both single marker analysis (SMA) and composite interval mapping (CIM) were used to identify QTL for WLT. Seventeen markers in Population 1 and 15 markers in Population 2 were significantly ( p <0.0001) associated with WLT in SMA. Many of these markers were linked to Rps genes or QTL conferring resistance to Phytophthora sojae Kaufmann and Gerdemann. Five markers, Satt599 on linkage group (LG) A1, Satt160, Satt269, and Satt252 on LG F, and Satt485 on LG N, were significant ( p <0.0001) for WLT in both populations. With CIM, a WLT QTL was found close to the marker Satt385 on LG A1 in Population 1 in 2003. This QTL explained 10% of the phenotypic variation and the allele that increased WLT came from Archer. In Population 2 in 2002, a WLT QTL was located near the marker Satt269 on LG F. This QTL explained 16% of the phenotypic variation and the allele that increased WLT also came from Archer. [ABSTRACT FROM AUTHOR]

We have developed a highly informative set of single-nucleotide polymorphism (SNP) assays designed for linkage mapping of the human genome. These assays were developed on a robust multiplexed assay system to provide a combination of very high accuracy and data completeness with high throughput for linkage studies. The linkage panel is comprised of approximately 4,700 SNPs with 0.39 average minor allele frequency and 624-kb average spacing. Based on almost 2 million genotypes, data quality was shown to be extremely high, with a 99.94% call rate, >99.99% reproducibility and 99.995% genotypes consistent with mendelian inheritance. We constructed a genetic map with an average 1.5-cM resolution using series of 28 CEPH pedigrees. The relative information content of this panel was higher than those of commonly used STR marker panels. The potent combination of this SNP linkage panel with the multiplexed assay system provides a previously unattainable level of performance for linkage studies. [ABSTRACT FROM AUTHOR]

A correction to the article "Identification of QTLs associated with resistance to soybean cyst nematode races 2, 3 and 5 in soybean PI 90763" that was published in volume 111, 2005 issue of "Theoretical and Applied Genetics" journal is presented.