Genetic Analysis and Related Gene Primary Mapping of Heat Stress Tolerance in Cucumber Using Bulked Segregant Analysis

Heat stress (HS) negatively influences plant development and growth, especially production and quality. Cucumber is a widely cultivated plant in the gourd family Cucurbitaceae that is often exposed to high temperatures during summer and protected cultivation. In this study, we performed whole-genome re-sequencing of two pools, one heat-tolerant and one heat-sensitive, of the F2 population derived from L-9 (heat-resistant) and A-16 (heat-sensitive). The genetic analysis showed that the heat resistance of L-9 cucumber seedlings was controlled by a single recessive gene. By combining bulked segregant analysis (BSA) technology, the crucial gene related to HS was preliminarily mapped to a 1.08-Mb region on chromosome 1. To fine-map the locus, Indel markers were designed according to the genomic sequence. Finally, the gene was narrowed to a 550-kb region flanked by two Indel markers, namely Indel-H90 and Indel-H224, that contained 56 candidate genes. Re-sequencing results indicated that 10 candidate genes among the 56 in the candidate region showed single base pair differences in the exons. Quantitative reverse-transcription polymerase chain reaction showed that 6 genes among the 10 candidate genes were significantly decreased when exposed to high temperatures. These results not only were useful for the isolation and characterization of the key genes involved in HS but also provided a basis for understanding the mechanism of heat tolerance regulation.

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Genetic analysis and mapping of a thermosensitive genic male sterility gene, tms6(t), in rice (Oryza sativa L.)

Genome ◽

10.1139/g09-092 ◽

2010 ◽

Vol 53 (2) ◽

pp. 119-124 ◽

Cited By ~ 7

Author(s):

Xia Liu ◽

Xihong Li ◽

Xin Zhang ◽

Songwen Wang

Keyword(s):

Genetic Analysis ◽

Molecular Mapping ◽

Oryza Sativa L ◽

Bulked Segregant Analysis ◽

Recessive Gene ◽

Male Sterile ◽

Chromosome 10 ◽

Physical Maps ◽

Specific Temperature ◽

Simple Sequence

Thermosensitive genic male-sterile (TGMS) rice is widely used in hybrid rice production. Because of its specific temperature requirement, it can be used only in a narrow rice-growing zone in Asia. A newly discovered TGMS line, G20S, has an opposite phenotype compared with normal TGMS lines. G20S is completely sterile when the temperature is lower than 29.5 °C. Thus, it can be widely used in a larger area. Genetic analysis indicated that the sterility of G20S was controlled by a single recessive gene that was named tms6(t). An F2 population from the cross between G20S and Jing226 was developed and used for molecular mapping of the tms6(t) gene. The simple sequence repeat technique, combined with bulked segregant analysis, was used to screen markers linked to the target gene, and linkage markers such as RM216, RM2504, RM3152, and RM4455 were identified. These markers are all located on chromosome 10; therefore, tms6(t) was subsequently mapped on chromosome 10. Co-segregation analysis using the F2 population showed that two of these markers, RM3152 and RM4455, were closely linked to tms6(t) at distances of 3.00 cM and 1.10 cM, respectively. Additionally, integration of the genetic and physical maps showed that there were 15 BAC/PAC clones overlapping between RM3152 and RM4455, and tms6(t) was mapped to an interval of 1455 kb.

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QTL Mapping and Identification of Candidate Genes for Heat Tolerance at the Flowering Stage in Rice

Frontiers in Genetics ◽

10.3389/fgene.2020.621871 ◽

2021 ◽

Vol 11 ◽

Author(s):

Lei Chen ◽

Qiang Wang ◽

Maoyan Tang ◽

Xiaoli Zhang ◽

Yinghua Pan ◽

...

Keyword(s):

Heat Stress ◽

Abiotic Stress ◽

High Temperature ◽

Candidate Genes ◽

Heat Tolerance ◽

Bulked Segregant Analysis ◽

Abiotic Stress Tolerance ◽

Chromosome 8 ◽

Flowering Stage ◽

Heat Tolerant

High-temperature stress can cause serious abiotic damage that limits the yield and quality of rice. Heat tolerance (HT) during the flowering stage of rice is a key trait that can guarantee a high and stable yield under heat stress. HT is a complex trait that is regulated by multiple quantitative trait loci (QTLs); however, few underlying genes have been fine mapped and cloned. In this study, the F2:3 population derived from a cross between Huanghuazhan (HHZ), a heat-tolerant cultivar, and 9311, a heat-sensitive variety, was used to map HT QTLs during the flowering stage in rice. A new major QTL, qHTT8, controlling HT was identified on chromosome 8 using the bulked-segregant analysis (BSA)-seq method. The QTL qHTT8 was mapped into the 3,555,000–4,520,000 bp, which had a size of 0.965 Mb. The candidate region of qHTT8 on chromosome 8 contained 65 predicted genes, and 10 putative predicted genes were found to be associated with abiotic stress tolerance. Furthermore, qRT-PCR was performed to analyze the differential expression of these 10 genes between HHZ and 9311 under high temperature conditions. LOC_Os08g07010 and LOC_Os08g07440 were highly induced in HHZ compared with 9311 under heat stress. Orthologous genes of LOC_Os08g07010 and LOC_Os08g07440 in plants played a role in abiotic stress, suggesting that they may be the candidate genes of qHTT8. Generally, the results of this study will prove useful for future efforts to clone qHTT8 and breed heat-tolerant varieties of rice using marker-assisted selection.

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Identification of a novel locus, BPH38(t), conferring resistance to brown planthopper (Nilaparvata lugens Stal.) using early backcross population in rice (Oryza sativa L.)

Euphytica ◽

10.1007/s10681-019-2506-2 ◽

2019 ◽

Vol 215 (11) ◽

Cited By ~ 7

Author(s):

C. H. Balachiranjeevi ◽

G. D. Prahalada ◽

A. Mahender ◽

Md. Jamaloddin ◽

M. A. L. Sevilla ◽

...

Keyword(s):

Genetic Analysis ◽

Candidate Genes ◽

Brown Planthopper ◽

Snp Markers ◽

Superior Performance ◽

Chromosome 1 ◽

World Population ◽

Recurrent Parent ◽

Resistance Locus ◽

Backcross Population

Abstract Rice is the most important staple food crop, and it feeds more than half of the world population. Brown planthopper (BPH) is a major insect pest of rice that causes 20–80% yield loss through direct and indirect damage. The identification and use of BPH resistance genes can efficiently manage BPH. A molecular marker-based genetic analysis of BPH resistance was carried out using 101 BC1F5 mapping population derived from a cross between a BPH-resistant indica variety Khazar and an elite BPH-susceptible line Huang–Huan–Zhan. The genetic analysis indicated the existence of Mendelian segregation for BPH resistance. A total of 702 high-quality polymorphic single nucleotide polymorphism (SNP) markers, genotypic data, and precisely estimated BPH scores were used for molecular mapping, which resulted in the identification of the BPH38(t) locus on the long arm of chromosome 1 between SNP markers 693,369 and id 10,112,165 of 496.2 kb in size with LOD of 20.53 and phenotypic variation explained of 35.91%. A total of 71 candidate genes were predicted in the detected locus. Among these candidate genes, LOC_Os01g37260 was found to belong to the FBXL class of F-box protein possessing the LRR domain, which is reported to be involved in biotic stress resistance. Furthermore, background analysis and phenotypic selection resulted in the identification of introgression lines (ILs) possessing at least 90% recurrent parent genome recovery and showing superior performance for several agro-morphological traits. The BPH resistance locus and ILs identified in the present study will be useful in marker-assisted BPH resistance breeding programs.

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Insights into the heat-responsive transcriptional network of tomato contrasting genotypes

Plant Genetic Resources ◽

10.1017/s1479262121000083 ◽

2021 ◽

Vol 19 (1) ◽

pp. 44-57

Author(s):

Sirine Werghi ◽

Charfeddine Gharsallah ◽

Nishi Kant Bhardwaj ◽

Hatem Fakhfakh ◽

Faten Gorsane

Keyword(s):

Heat Stress ◽

Heat Shock ◽

Candidate Genes ◽

Expression Patterns ◽

Response Strategies ◽

Transcriptional Reprogramming ◽

Genes Encoding ◽

Breeding Programmes ◽

Gene Transcripts ◽

Resource Data

AbstractDuring recent decades, global warming has intensified, altering crop growth, development and survival. To overcome changes in their environment, plants undergo transcriptional reprogramming to activate stress response strategies/pathways. To evaluate the genetic bases of the response to heat stress, Conserved DNA-derived Polymorphism (CDDP) markers were applied across tomato genome of eight cultivars. Despite scattered genotypes, cluster analysis allowed two neighbouring panels to be discriminate. Tomato CDDP-genotypic and visual phenotypic assortment permitted the selection of two contrasting heat-tolerant and heat-sensitive cultivars. Further analysis explored differential expression in transcript levels of genes, encoding heat shock transcription factors (HSFs, HsfA1, HsfA2, HsfB1), members of the heat shock protein (HSP) family (HSP101, HSP17, HSP90) and ascorbate peroxidase (APX) enzymes (APX1, APX2). Based on discriminating CDDP-markers, a protein functional network was built allowing prediction of candidate genes and their regulating miRNA. Expression patterns analysis revealed that miR156d and miR397 were heat-responsive showing a typical inverse relation with the abundance of their target gene transcripts. Heat stress is inducing a set of candidate genes, whose expression seems to be modulated through a complex regulatory network. Integrating genetic resource data is required for identifying valuable tomato genotypes that can be considered in marker-assisted breeding programmes to improve tomato heat tolerance.

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Isolation and Characterization Of Rice R Genes: Evidence for Distinct Evolutionary Paths in Rice and Maize

Genetics ◽

10.1093/genetics/142.3.1021 ◽

1996 ◽

Vol 142 (3) ◽

pp. 1021-1031 ◽

Cited By ~ 3

Author(s):

Jianping Hu ◽

Beth Anderson ◽

Susan R Wessler

Keyword(s):

Gene Family ◽

Gene Families ◽

Chromosome 1 ◽

R Gene ◽

R Genes ◽

Helix Loop Helix ◽

Isolation And Characterization ◽

Undetermined Function ◽

Evolutionary Paths

Abstract R and B genes and their homologues encode basic helix-loop-helix (bHLH) transcriptional activators that regulate the anthocyanin biosynthetic pathway in flowering plants. In maize, R/B genes comprise a very small gene family whose organization reflects the unique evolutionary history and genome architecture of maize. To know whether the organization of the R gene family could provide information about the origins of the distantly related grass rice, we characterized members of the R gene family from rice Oryza sativa. Despite being a true diploid, O. sativa has at least two R genes. An active homologue (Ra) with extensive homology with other R genes is located at a position on chromosome 4 previously shown to be in synteny with regions of maize chromosomes 2 and 10 that contain the B and R loci, respectively. A second rice R gene (Rb) of undetermined function was identified on chromosome 1 and found to be present only in rice species with AA genomes. All non-AA species have but one R gene that is Ra-like. These data suggest that the common ancestor shared by maize and rice had a single R gene and that the small R gene families of grasses have arisen recently and independently.

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Genotype-by-environment interaction in Holstein heifer fertility traits using single-step genomic reaction norm models

BMC Genomics ◽

10.1186/s12864-021-07496-3 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Rui Shi ◽

Luiz Fernando Brito ◽

Aoxing Liu ◽

Hanpeng Luo ◽

Ziwei Chen ◽

...

Keyword(s):

Heat Stress ◽

Dairy Cattle ◽

Candidate Genes ◽

Heat Tolerance ◽

Reaction Norm ◽

Single Step ◽

Conception Rate ◽

Critical Periods ◽

Genotype By Environment ◽

Fertility Traits

Abstract Background The effect of heat stress on livestock production is a worldwide issue. Animal performance is influenced by exposure to harsh environmental conditions potentially causing genotype-by-environment interactions (G × E), especially in highproducing animals. In this context, the main objectives of this study were to (1) detect the time periods in which heifer fertility traits are more sensitive to the exposure to high environmental temperature and/or humidity, (2) investigate G × E due to heat stress in heifer fertility traits, and, (3) identify genomic regions associated with heifer fertility and heat tolerance in Holstein cattle. Results Phenotypic records for three heifer fertility traits (i.e., age at first calving, interval from first to last service, and conception rate at the first service) were collected, from 2005 to 2018, for 56,998 Holstein heifers raised in 15 herds in the Beijing area (China). By integrating environmental data, including hourly air temperature and relative humidity, the critical periods in which the heifers are more sensitive to heat stress were located in more than 30 days before the first service for age at first calving and interval from first to last service, or 10 days before and less than 60 days after the first service for conception rate. Using reaction norm models, significant G × E was detected for all three traits regarding both environmental gradients, proportion of days exceeding heat threshold, and minimum temperature-humidity index. Through single-step genome-wide association studies, PLAG1, AMHR2, SP1, KRT8, KRT18, MLH1, and EOMES were suggested as candidate genes for heifer fertility. The genes HCRTR1, AGRP, PC, and GUCY1B1 are strong candidates for association with heat tolerance. Conclusions The critical periods in which the reproductive performance of heifers is more sensitive to heat stress are trait-dependent. Thus, detailed analysis should be conducted to determine this particular period for other fertility traits. The considerable magnitude of G × E and sire re-ranking indicates the necessity to consider G × E in dairy cattle breeding schemes. This will enable selection of more heat-tolerant animals with high reproductive efficiency under harsh climatic conditions. Lastly, the candidate genes identified to be linked with response to heat stress provide a better understanding of the underlying biological mechanisms of heat tolerance in dairy cattle.

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Expression of candidate genes for residual feed intake in tropically adapted Bos taurus and Bos indicus bulls under thermoneutral and heat stress environmental conditions

Journal of Thermal Biology ◽

10.1016/j.jtherbio.2021.102998 ◽

2021 ◽

pp. 102998

Author(s):

Bianca Vilela Pires ◽

Nedenia Bonvino Stafuzza ◽

Luara Afonso de Freitas ◽

Maria Eugênia Zerlotti Mercadante ◽

Ester Silveira Ramos ◽

...

Keyword(s):

Heat Stress ◽

Candidate Genes ◽

Feed Intake ◽

Environmental Conditions ◽

Bos Taurus ◽

Bos Indicus ◽

Residual Feed Intake

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Molecular Markers for Rapidly Identifying Candidate Genes in Chlamydomonas reinhardtii: ERY1 and ERY2 Encode Chloroplast Ribosomal Proteins

Genetics ◽

10.1093/genetics/164.4.1345 ◽

2003 ◽

Vol 164 (4) ◽

pp. 1345-1353

Author(s):

Amber K Bowers ◽

Jennifer A Keller ◽

Susan K Dutcher

Keyword(s):

Molecular Markers ◽

Chlamydomonas Reinhardtii ◽

Candidate Genes ◽

Splice Site ◽

Genomic Dna ◽

Ribosomal Proteins ◽

Genomic Sequence ◽

Point Mutations ◽

Acceptor Site ◽

Wild Type

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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Identification of Candidate Gene for Internode Length in Rice to Enhance Resistance to Lodging Using QTL Analysis

Plants ◽

10.3390/plants10071369 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1369

Author(s):

Dan-Dan Zhao ◽

Ju-Hyeong Son ◽

Muhammad Farooq ◽

Kyung-Min Kim

Keyword(s):

Candidate Genes ◽

Qtl Analysis ◽

Middle Part ◽

Internode Length ◽

Stem Diameter ◽

Chromosome 1 ◽

Doubled Haploid Population ◽

Lodging Resistance ◽

Cytochrome P450 Family ◽

Uppermost Internode

Internode length and stem diameter are the primary traits affecting the lodging resistance of rice. Traits related to the length of the panicle (LP), uppermost internode (LUI), second internode (LSI), third internode (LTI), fourth internode (LFI), lowest internode (LLI) as well as stem diameter at the uppermost internode (SDUI), second internode (SDSI), third internode (SDTI), fourth internode (SDFI), and lowest internode (SDLI) in 120 Cheongcheong/Nagdong doubled haploid population were investigated using a quantitative trait locus (QTL) analysis. Thirty-four QTL regions affected LP and the length of each internode. Twenty-six QTL regions were associated with the stem diameter of each internode. RM12285-RM212 on chromosome 1 contained 10 QTLs related to the internode length, which have overlapped for over 2 years. Twenty-three candidate genes were screened using mark interval. Among the candidate genes, Os01g0803900, named OsCYPq1, which is in the Cytochrome P450 family, might be involved in gibberellins (GA) synthesis. GA is an essential plant growth regulator that affects plant height. OsCYPq1 catalyzes oxidation steps in the middle part of the GA pathway. OsCYPq1 is expected to provide valuable information to improve the marker assessment for target traits and QTL gene cloning in rice.

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The embryonic RNA helicase gene (ERH): a new member of the DEAD box family of RNA helicases

Biochemical Journal ◽

10.1042/bj3080839 ◽

1995 ◽

Vol 308 (3) ◽

pp. 839-846 ◽

Cited By ~ 15

Author(s):

J Sowden ◽

W Putt ◽

K Morrison ◽

R Beddington ◽

Y Edwards

Keyword(s):

Expression Profile ◽

Sequence Similarity ◽

Rna Helicase ◽

Chromosome 1 ◽

Rna Helicases ◽

High Sequence Similarity ◽

Dead Box ◽

Isolation And Characterization ◽

Helicase Gene ◽

The Dead

DEAD box proteins share several highly conserved motifs including the characteristic Asp-Glu-Ala-Asp (D-E-A-D in the amino acid single-letter code) motif and have established or putative ATP-dependent RNA helicase activity. These proteins are implicated in a range of cellular processes that involve regulation of RNA function, including translation initiation, RNA splicing and ribosome assembly. Here we describe the isolation and characterization of an embryonic RNA helicase gene, ERH, which maps to mouse chromosome 1 and encodes a new member of the DEAD box family of proteins. The predicted ERH protein shows high sequence similarity to the testes-specific mouse PL10 and to the maternally acting Xenopus An3 helicase proteins. The ERH expression profile is similar, to that of An3, which localizes to the animal hemisphere of oocytes and is abundantly expressed in the embryo. ERH is expressed in oocytes and is a ubiquitous mRNA in the 9 days-post-conception embryo, and at later stages of development shows a more restricted pattern of expression in brain and kidney. The similarities in sequence and in expression profile suggest that ERH is the murine equivalent of the Xenopus An3 gene, and we propose that ERH plays a role in translational activation of mRNA in the oocyte and early embryo.

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