scholarly journals Development of New Candidate Gene and EST-Based Molecular Markers for Gossypium Species

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Ramesh Buyyarapu ◽  
Ramesh V. Kantety ◽  
John Z. Yu ◽  
Sukumar Saha ◽  
Govind C. Sharma

New source of molecular markers accelerate the efforts in improving cotton fiber traits and aid in developing high-density integrated genetic maps. We developed new markers based on candidate genes and G. arboreum EST sequences that were used for polymorphism detection followed by genetic and physical mapping. Nineteen gene-based markers were surveyed for polymorphism detection in 26 Gossypium species. Cluster analysis generated a phylogenetic tree with four major sub-clusters for 23 species while three species branched out individually. CAP method enhanced the rate of polymorphism of candidate gene-based markers between G. hirsutum and G. barbadense. Two hundred A-genome based SSR markers were designed after datamining of G. arboreum EST sequences (Mississippi Gossypium arboreum  EST-SSR: MGAES). Over 70% of MGAES markers successfully produced amplicons while 65 of them demonstrated polymorphism between the parents of G. hirsutum and G. barbadense RIL population and formed 14 linkage groups. Chromosomal localization of both candidate gene-based and MGAES markers was assisted by euploid and hypoaneuploid CS-B analysis. Gene-based and MGAES markers were highly informative as they were designed from candidate genes and fiber transcriptome with a potential to be integrated into the existing cotton genetic and physical maps.

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi30-vi30
Author(s):  
Anne Schuster ◽  
Virginie Neirinckx ◽  
Eliane Klein ◽  
Petr V Nazarov ◽  
Anais Oudin ◽  
...  

Abstract BACKGROUND A major hallmark of glioblastoma (GBM) is its invasive capacity, contributing to its aggressive behaviour. Invasive cells cannot be easily removed by surgery or irradiation and eventually result in lethal recurrence. A better understanding of the invasion process and the key molecular players underlying the invasive potential of GBM may lead to the identification of new therapeutic targets for GBM patients. MATERIAL AND METHODS To identify candidate genes responsible for invasion, a genome-wide shRNA screen was performed in patient-derived GBM cultures. The most promising candidate was validated in in vitro invasion assays, ex vivo brain slice cultures and in vivo orthotopic xenografts in mice. Gene knockdown in invasive GBM cells was compared with overexpression in non-invasive cells. RNAseq of knockdown cells, along with the generation of deletion constructs were applied to uncover the mechanisms regulating invasion. RESULTS A zinc-finger domain containing protein was identified as an invasion essential candidate gene. Knockdown of this gene confirmed a strong impact on invasion in highly invasive GBM cells. In contrast, gene overexpression switched non-invasive GBM cells to an invasive phenotype. Deletion of one or both zinc-finger motifs decreased invasion indicating that both are essential for regulating invasion. Mutation of the nuclear localisation signal resulted in retention of the protein in the cytoplasm and loss of the invasion phenotype demonstrating that the protein activity is required in the nucleus. Gene expression analyses revealed that invasion-related genes are significantly regulated by the candidate gene once it is localized in the nucleus. CONCLUSION We identified a zinc-finger containing protein as a novel driver of GBM invasion, presumably through transcription factor activity resulting in the induction of an invasive transcriptional program. This protein and its downstream pathway may represent novel promising targets to overcome invasive capacities in GBM.


2019 ◽  
Vol 21 (Supplement_3) ◽  
pp. iii48-iii48
Author(s):  
A Schuster ◽  
V Neirinckx ◽  
E Klein ◽  
P V Nazarov ◽  
A Oudin ◽  
...  

Abstract BACKGROUND A major hallmark of glioblastoma (GBM) is its highly invasive capacity, contributing to its aggressive behaviour. Since invasive cells cannot be easily removed by surgery or irradiation, they are left behind and eventually result in lethal recurrence. Therefore, a better understanding of the invasion process and of the key molecular players underlying the invasive capacities of GBM may lead to the identification of new therapeutic targets for GBM patients. MATERIAL AND METHODS To identify candidate genes responsible for invasion, a genome-wide shRNA screen was performed in patient-derived GBM sphere cultures. The phenotype of the most promising candidate was validated in in vitro invasion assays, ex vivo brain slice cultures and in vivo orthotopic xenografts in mice. Gene knockdown in invasive GBM cell lines was compared with overexpression in non-invasive cells. RNA sequencing of knockdown cells, along with the generation of deletion constructs were applied to uncover the mechanisms regulating invasion. RESULTS Through a whole genome shRNA screen, a zinc-finger containing protein was identified as an invasion essential candidate gene. Knockdown of this gene confirmed a strong decrease in invasion capacity in two highly invasive GBM cell lines. In contrast, gene overexpression switched non-invasive GBM cells to an invasive phenotype. Deletion of either one or both zinc-finger motifs led to decreased invasion indicating that the two zinc-finger motifs are essential for regulating invasion. Mutation of the nuclear localisation signal resulted in retention of the protein in the cytoplasm and loss of the invasion phenotype demonstrating that the protein activity is required in the nucleus. Gene expression analyses revealed that invasion-related genes are significantly regulated by the candidate gene once it is localized in the nucleus. CONCLUSION We identified a zinc-finger containing protein as a novel driver of GBM invasion, presumably through a transcription factor activity resulting in the induction of an invasive transcriptional program. This protein and its downstream pathway may represent a novel promising target to overcome invasive capacities in GBM.


2017 ◽  
Vol 7 (7) ◽  
pp. 2391-2403 ◽  
Author(s):  
Amanda S Lobell ◽  
Rachel R Kaspari ◽  
Yazmin L Serrano Negron ◽  
Susan T Harbison

Abstract Ovariole number has a direct role in the number of eggs produced by an insect, suggesting that it is a key morphological fitness trait. Many studies have documented the variability of ovariole number and its relationship to other fitness and life-history traits in natural populations of Drosophila. However, the genes contributing to this variability are largely unknown. Here, we conducted a genome-wide association study of ovariole number in a natural population of flies. Using mutations and RNAi-mediated knockdown, we confirmed the effects of 24 candidate genes on ovariole number, including a novel gene, anneboleyn (formerly CG32000), that impacts both ovariole morphology and numbers of offspring produced. We also identified pleiotropic genes between ovariole number traits and sleep and activity behavior. While few polymorphisms overlapped between sleep parameters and ovariole number, 39 candidate genes were nevertheless in common. We verified the effects of seven genes on both ovariole number and sleep: bin3, blot, CG42389, kirre, slim, VAChT, and zfh1. Linkage disequilibrium among the polymorphisms in these common genes was low, suggesting that these polymorphisms may evolve independently.


Genes ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 604
Author(s):  
Paolo Vitale ◽  
Fabio Fania ◽  
Salvatore Esposito ◽  
Ivano Pecorella ◽  
Nicola Pecchioni ◽  
...  

Traits such as plant height (PH), juvenile growth habit (GH), heading date (HD), and tiller number are important for both increasing yield potential and improving crop adaptation to climate change. In the present study, these traits were investigated by using the same bi-parental population at early (F2 and F2-derived F3 families) and late (F6 and F7, recombinant inbred lines, RILs) generations to detect quantitative trait loci (QTLs) and search for candidate genes. A total of 176 and 178 lines were genotyped by the wheat Illumina 25K Infinium SNP array. The two genetic maps spanned 2486.97 cM and 3732.84 cM in length, for the F2 and RILs, respectively. QTLs explaining the highest phenotypic variation were found on chromosomes 2B, 2D, 5A, and 7D for HD and GH, whereas those for PH were found on chromosomes 4B and 4D. Several QTL detected in the early generations (i.e., PH and tiller number) were not detected in the late generations as they were due to dominance effects. Some of the identified QTLs co-mapped to well-known adaptive genes (i.e., Ppd-1, Vrn-1, and Rht-1). Other putative candidate genes were identified for each trait, of which PINE1 and PIF4 may be considered new for GH and TTN in wheat. The use of a large F2 mapping population combined with NGS-based genotyping techniques could improve map resolution and allow closer QTL tagging.


Genetics ◽  
1996 ◽  
Vol 142 (2) ◽  
pp. 537-548 ◽  
Author(s):  
Michael W Nachman ◽  
Gary A Churchill

Abstract If loci are randomly distributed on a physical map, the density of markers on a genetic map will be inversely proportional to recombination rate. First proposed by MARY LYON, we have used this idea to estimate recombination rates from the Drosophila melanogaster linkage map. These results were compared with results of two other studies that estimated regional recombination rates in D. melanogaster using both physical and genetic maps. The three methods were largely concordant in identifying large-scale genomic patterns of recombination. The marker density method was then applied to the Mus musculus microsatellite linkage map. The distribution of microsatellites provided evidence for heterogeneity in recombination rates. Centromeric regions for several mouse chromosomes had significantly greater numbers of markers than expected, suggesting that recombination rates were lower in these regions. In contrast, most telomeric regions contained significantly fewer markers than expected. This indicates that recombination rates are elevated at the telomeres of many mouse chromosomes and is consistent with a comparison of the genetic and cytogenetic maps in these regions. The density of markers on a genetic map may provide a generally useful way to estimate regional recombination rates in species for which genetic, but not physical, maps are available.


Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 192
Author(s):  
Xinghai Duan ◽  
Bingxing An ◽  
Lili Du ◽  
Tianpeng Chang ◽  
Mang Liang ◽  
...  

The objective of the present study was to perform a genome-wide association study (GWAS) for growth curve parameters using nonlinear models that fit original weight–age records. In this study, data from 808 Chinese Simmental beef cattle that were weighed at 0, 6, 12, and 18 months of age were used to fit the growth curve. The Gompertz model showed the highest coefficient of determination (R2 = 0.954). The parameters’ mature body weight (A), time-scale parameter (b), and maturity rate (K) were treated as phenotypes for single-trait GWAS and multi-trait GWAS. In total, 9, 49, and 7 significant SNPs associated with A, b, and K were identified by single-trait GWAS; 22 significant single nucleotide polymorphisms (SNPs) were identified by multi-trait GWAS. Among them, we observed several candidate genes, including PLIN3, KCNS3, TMCO1, PRKAG3, ANGPTL2, IGF-1, SHISA9, and STK3, which were previously reported to associate with growth and development. Further research for these candidate genes may be useful for exploring the full genetic architecture underlying growth and development traits in livestock.


Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 318
Author(s):  
Tae-Ho Ham ◽  
Yebin Kwon ◽  
Yoonjung Lee ◽  
Jisu Choi ◽  
Joohyun Lee

We conducted a genome-wide association study (GWAS) of cold tolerance in a collection of 127 rice accessions, including 57 Korean landraces at the seedling stage. Cold tolerance of rice seedlings was evaluated in a growth chamber under controlled conditions and scored on a 0–9 scale, based on their low-temperature response and subsequent recovery. GWAS, together with principal component analysis (PCA) and kinship matrix analysis, revealed four quantitative trait loci (QTLs) on chromosomes 1, 4, and 5 that explained 16.5% to 18.5% of the variance in cold tolerance. The genomic region underlying the QTL on chromosome four overlapped with a previously reported QTL associated with cold tolerance in rice seedlings. Similarly, one of the QTLs identified on chromosome five overlapped with a previously reported QTL associated with seedling vigor. Subsequent bioinformatic and haplotype analyses revealed three candidate genes affecting cold tolerance within the linkage disequilibrium (LD) block of these QTLs: Os01g0357800, encoding a pentatricopeptide repeat (PPR) domain-containing protein; Os05g0171300, encoding a plastidial ADP-glucose transporter; and Os05g0400200, encoding a retrotransposon protein, Ty1-copia subclass. The detected QTLs and further evaluation of these candidate genes in the future will provide strategies for developing cold-tolerant rice in breeding programs.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jose Miguel Soriano ◽  
Pasqualina Colasuonno ◽  
Ilaria Marcotuli ◽  
Agata Gadaleta

AbstractThe genetic improvement of durum wheat and enhancement of plant performance often depend on the identification of stable quantitative trait loci (QTL) and closely linked molecular markers. This is essential for better understanding the genetic basis of important agronomic traits and identifying an effective method for improving selection efficiency in breeding programmes. Meta-QTL analysis is a useful approach for dissecting the genetic basis of complex traits, providing broader allelic coverage and higher mapping resolution for the identification of putative molecular markers to be used in marker-assisted selection. In the present study, extensive QTL meta-analysis was conducted on 45 traits of durum wheat, including quality and biotic and abiotic stress-related traits. A total of 368 QTL distributed on all 14 chromosomes of genomes A and B were projected: 171 corresponded to quality-related traits, 127 to abiotic stress and 71 to biotic stress, of which 318 were grouped in 85 meta-QTL (MQTL), 24 remained as single QTL and 26 were not assigned to any MQTL. The number of MQTL per chromosome ranged from 4 in chromosomes 1A and 6A to 9 in chromosome 7B; chromosomes 3A and 7A showed the highest number of individual QTL (4), and chromosome 7B the highest number of undefined QTL (4). The recently published genome sequence of durum wheat was used to search for candidate genes within the MQTL peaks. This work will facilitate cloning and pyramiding of QTL to develop new cultivars with specific quantitative traits and speed up breeding programs.


2021 ◽  
Vol 11 (1) ◽  
pp. 59
Author(s):  
Kirsten Voorhies ◽  
Joanne E. Sordillo ◽  
Michael McGeachie ◽  
Elizabeth Ampleford ◽  
Alberta L. Wang ◽  
...  

An unaddressed and important issue is the role age plays in modulating response to short acting β2-agonists in individuals with asthma. The objective of this study was to identify whether age modifies genetic associations of single nucleotide polymorphisms (SNPs) with bronchodilator response (BDR) to β2-agonists. Using three cohorts with a total of 892 subjects, we ran a genome wide interaction study (GWIS) for each cohort to examine SNP by age interactions with BDR. A fixed effect meta-analysis was used to combine the results. In order to determine if previously identified BDR SNPs had an age interaction, we also examined 16 polymorphisms in candidate genes from two published genome wide association studies (GWAS) of BDR. There were no significant SNP by age interactions on BDR using the genome wide significance level of 5 × 10−8. Using a suggestive significance level of 5 × 10−6, three interactions, including one for a SNP within PRAG1 (rs4840337), were significant and replicated at the significance level of 0.05. Considering candidate genes from two previous GWAS of BDR, three SNPs (rs10476900 (near ADRB2) [p-value = 0.009], rs10827492 (CREM) [p-value = 0.02], and rs72646209 (NCOA3) [p-value = 0.02]) had a marginally significant interaction with age on BDR (p < 0.05). Our results suggest age may be an important modifier of genetic associations for BDR in asthma.


Genetics ◽  
2003 ◽  
Vol 164 (4) ◽  
pp. 1345-1353
Author(s):  
Amber K Bowers ◽  
Jennifer A Keller ◽  
Susan K Dutcher

Abstract To take advantage of available expressed sequence tags and genomic sequence, we have developed 64 PCR-based molecular markers in Chlamydomonas reinhardtii that map to the 17 linkage groups. These markers will allow the rapid association of a candidate gene sequence with previously identified mutations. As proof of principle, we have identified the genes encoded by the ERY1 and ERY2 loci. Mendelian mutations that confer resistance to erythromycin define three unlinked nuclear loci in C. reinhardtii. Candidate genes ribosomal protein L4 (RPL4) and L22 (RPL22) are tightly linked to the ERY1 locus and ERY2 locus, respectively. Genomic DNA for RPL4 from wild type and five mutant ery1 alleles was amplified and sequenced and three different point mutations were found. Two different glycine residues (G102 and G112) are replaced by aspartic acid and both are in the unstructured region of RPL4 that lines the peptide exit tunnel of the chloroplast ribosome. The other two alleles change a splice site acceptor site. Genomic DNA for RPL22 from wild type and three mutant ery2 alleles was amplified and sequenced and revealed three different point mutations. Two alleles have premature stop codons and one allele changes a splice site acceptor site.


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