<Emphasis Type="Italic">Methylophaga muralis</Emphasis> Bur 1, a haloalkaliphilic methylotroph isolated from the Khilganta soda lake (Southern Transbaikalia,Buryat Republic)

A haloalkaliphilic restricted facultative methylotroph, strain Bur 1, which used methanol, methylated amines, and fructose as carbon and energy sources, was isolated from the soda Lake Khilganta (Buryat Republic, Russia). The cells were gram-negative non-spore-forming, motile rods reproducing by binary fission. The organism was aerobic, reduced nitrates to nitrites. Growth occurred at temperatures from 4 to 37°C (optimum at 25–29°C), pH 7.5–10.5 (optimum at 8.5–9.5), and NaCl concentration in the medium from 0.05 to 10.0% NaCl (optimum at 3–4%). Ectoine, glutamate, and sucrose were accumulated as osmoprotectants. Activity of the enzymes of de novo ectoine biosynthesis were detected. The organism utilized C₁ compounds via the KDPG variant of the ribulose monophosphate pathway. The DNA G + C content was 44.67 mol %. Based on the similarity of the 16S rRNA gene sequences (94.7–99.1%) and the results of DNA–DNA hybridization (24–74%) with type strains of the neutrophilic and alkaliphilic Methylophaga species, the isolate was identified as Methylophaga muralis Bur 1 (VKM B-3046 = DSM 103617). The genome of M. muralis Bur 1 contained 2585 protein-encoding genes; 634 proteins with unidentified functions were predicted. Three rRNAs (5S, 16S, and 23S) and 38 tRNAs were identified. Apart from the mxaFJGIRSACKLDEH classical cluster of methanol oxidation genes, the xoxF gene was found. Methylamine was oxidized to formaldehyde by methylamine dehydrogenase and via the N-methylglutamate pathway. Orthologs of type III glutamine synthetases were revealed in the genome. The operons of ectoine and sucrose biosynthesis, ectRABC-ask and sps-spp-fruK-ams, were found. The genomes of M. muralis Bur 1 and M. lonarensis MPL^T, unlike that of M. nitratireducenticrescens JAM1^T, were found to contain the genes encoding the proteins of bicarbonate transport.     

Kelch-motif containing acyl-CoA binding proteins AtACBP4 and AtACBP5 are differentially expressed and function in floral lipid metabolism

Key message

We herein demonstrated two of the Arabidopsis acyl-CoA-binding proteins (ACBPs), AtACBP4 and AtACBP5, both function in floral lipid metabolism and they may possibly play complementary roles in Arabidopsis microspore-to-pollen development. Histological analysis on transgenic Arabidopsis expressing β-glucuronidase driven from the AtACBP4 and AtACBP5 promoters, as well as, qRTPCR analysis revealed that AtACBP4 was expressed at stages 11–14 in the mature pollen, while AtACBP5 was expressed at stages 7–10 in the microspores and tapetal cells. Immunoelectron microscopy using AtACBP4- or AtACBP5-specific antibodies further showed that AtACBP4 and AtACBP5 were localized in the cytoplasm. Chemical analysis of bud wax and cutin using gas chromatographyflame ionization detector and GC-mass spectrometry analyses revealed the accumulation of cuticular waxes and cutin monomers in acbp4, acbp5 and acbp4acbp5 buds in comparison to the wild type (Col-0). Fatty acid profiling demonstrated a decline in stearic acid and an increase in linolenic acid in acbp4 and acbp4acbp5 buds, respectively, over Col-0. Analysis of inflorescences from acbp4 and acbp5 revealed that there was an increase of AtACBP5 expression in acbp4, and an increase of AtACBP4 expression in acbp5. Deletion analysis of the AtACBP4 and AtACBP5 5′-flanking regions indicated the minimal promoter activity for AtACBP4 (?145/+103) and AtACBP5 (?181/+81). Electrophoretic mobility shift assays identified a pollen-specific cis-acting element POLLEN1 (AGAAA) mapped at AtACBP4 (?157/?153) which interacted with nuclear proteins from flower and this was substantiated by DNase I footprinting.

Abstract

In Arabidopsis thaliana, six acyl-CoA-binding proteins (ACBPs), designated as AtACBP1 to AtACBP6, have been identified to function in plant stress and development. AtACBP4 and AtACBP5 represent the two largest proteins in the AtACBP family. Despite having kelch-motifs and sharing a common cytosolic subcellular localization, AtACBP4 and AtACBP5 differ in spatial and temporal expression. Histological analysis on transgenic Arabidopsis expressing β-glucuronidase driven from the respective AtACBP4 and AtACBP5 promoters, as well as, qRT-PCR analysis revealed that AtACBP4 was expressed at stages 11–14 in mature pollen, while AtACBP5 was expressed at stages 7–10 in the microspores and tapetal cells. Immunoelectron microscopy using AtACBP4- or AtACBP5-specific antibodies further showed that AtACBP4 and AtACBP5 were localized in the cytoplasm. Chemical analysis of bud wax and cutin using gas chromatography-flame ionization detector and GC-mass spectrometry analyses revealed the accumulation of cuticular waxes and cutin monomers in acbp4, acbp5 and acbp4acbp5 buds, in comparison to the wild type. Analysis of inflorescences from acbp4 and acbp5 revealed that there was an increase of AtACBP5 expression in acbp4, and an increase of AtACBP4 expression in acbp5. Deletion analysis of the AtACBP4 and AtACBP5 5′-flanking regions indicated the minimal promoter region for AtACBP4 (?145/+103) and AtACBP5 (?181/+81). Electrophoretic mobility shift assays identified a pollen-specific cis-acting element POLLEN1 (AGAAA) within AtACBP4 (?157/?153) which interacted with nuclear proteins from flower and this was substantiated by DNase I footprinting. These results suggest that AtACBP4 and AtACBP5 both function in floral lipidic metabolism and they may play complementary roles in Arabidopsis microspore-to-pollen development.

     

Enhanced expression of ginsenoside biosynthetic genes and in vitro ginsenoside production in elicited <Emphasis Type="Italic">Panax sikkimensis</Emphasis> (Ban) cell suspensions

Dual metabolite, i.e., ginsenoside and anthocyanin, co-accumulating cell suspensions of Panax sikkimensis were subjected to elicitation with culture filtrates of Serratia marcescens (SD 21), Bacillus subtilis (FL11), Trichoderma atroviridae (TA), and T. harzianum (TH) at 1.25% and 2.5% v/v for 1- and 3-week duration. The fungal-derived elicitors (TA and TH) did not significantly affect biomass accumulation; however, bacterial elicitors (SD 21 and FL11), especially SD 21, led to comparable loss in biomass growth. In terms of ginsenoside content, differential responses were observed. A maximum of 3.2-fold increase (222.2 mg/L) in total ginsenoside content was observed with the use of 2.5% v/v TH culture filtrate for 1 week. Similar ginsenoside accumulation was observed with the use of 1-week treatment with 2.5% v/v SD 21 culture filtrate (189.3 mg/L) with a 10-fold increase in intracellular Rg2 biosynthesis (31 mg/L). Real-time PCR analysis of key ginsenoside biosynthesis genes, i.e., FPS, SQS, DDS, PPDS, and PPTS, revealed prominent upregulation of particularly PPTS expression (20–23-fold), accounting for the observed enhancement in protopanaxatriol ginsenosides. However, none of the elicitors led to successful enhancement in in vitro anthocyanin accumulation as compared to control values.     

Phosphorus supply,arbuscular mycorrhizal fungal species,and plant genotype impact on the protective efficacy of mycorrhizal inoculation against wheat powdery mildew

A potential alternative strategy to chemical control of plant diseases could be the stimulation of plant defense by arbuscular mycorrhizal fungi (AMF). In the present study, the influence of three parameters (phosphorus supply, mycorrhizal inoculation, and wheat cultivar) on AMF protective efficiency against Blumeria graminis f. sp. tritici, responsible for powdery mildew, was investigated under controlled conditions. A 5-fold reduction (P/5) in the level of phosphorus supply commonly recommended for wheat in France improved Funneliformis mosseae colonization and promoted protection against B. graminis f. sp. tritici in a more susceptible wheat cultivar. However, a further decrease in P affected plant growth, even under mycorrhizal conditions. Two commercially available AMF inocula (F. mosseae, Solrize®) and one laboratory inoculum (Rhizophagus irregularis) were tested for mycorrhizal development and protection against B. graminis f. sp. tritici of two moderately susceptible and resistant wheat cultivars at P/5. Mycorrhizal levels were the highest with F. mosseae (38 %), followed by R. irregularis (19 %) and Solrize® (SZE, 8 %). On the other hand, the highest protection level against B. graminis f. sp. tritici was obtained with F. mosseae (74 %), followed by SZE (58 %) and R. irregularis (34 %), suggesting that inoculum type rather than mycorrhizal levels determines the protection level of wheat against B. graminis f. sp. tritici. The mycorrhizal protective effect was associated with a reduction in the number of conidia with haustorium and with an accumulation of polyphenolic compounds at B. graminis f. sp. tritici infection sites. Both the moderately susceptible and the most resistant wheat cultivar were protected against B. graminis f. sp. tritici infection by F. mosseae inoculation at P/5, although the underlying mechanisms appear rather different between the two cultivars. This study emphasizes the importance of taking into account the considered parameters when considering the use of AMF as biocontrol agents.     

Modulation of proline metabolic gene expression in <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis> under water-stressed conditions by a drought-mitigating <Emphasis Type="Italic">Pseudomonas putida</Emphasis> strain

Although amelioration of drought stress in plants by plant growth promoting rhizobacteria (PGPR) is a well reported phenomenon, the molecular mechanisms governing it are not well understood. We have investigated the role of a drought ameliorating PGPR strain, Pseudomonas putida GAP-P45 on the regulation of proline metabolic gene expression in Arabidopsis thaliana under water-stressed conditions. Indeed, we found that Pseudomonas putida GAP-P45 alleviates the effects of water-stress in A. thaliana by drastic changes in proline metabolic gene expression profile at different time points post stress induction. Quantitative real-time expression analysis of proline metabolic genes in inoculated plants under water-stressed conditions showed a delayed but prolonged up-regulation of the expression of genes involved in proline biosynthesis, i.e., ornithine-Δ-aminotransferase (OAT), Δ ¹ -pyrroline-5-carboxylate synthetase1 (P5CS1), Δ ¹ -pyrroline-5-carboxylate reductase (P5CR), as well as proline catabolism, i.e., proline dehydrogenase1 (PDH1) and Δ ¹ -pyrroline-5-carboxylate dehydrogenase (P5CDH). These observations were positively correlated with morpho-physiological evidences of water-stress mitigation in the plants inoculated with Pseudomonas putida GAP-P45 that showed better growth, increased fresh weight, enhanced plant water content, reduction in primary root length, enhanced chlorophyll content in leaves, and increased accumulation of endogenous proline. Our observations point towards PGPR-mediated enhanced proline turnover rate in A. thaliana under dehydration conditions.     

An alternative high-throughput staining method for detection of neutral lipids in green microalgae for biodiesel applications

A simple and high-throughput method for determining in situ intracellular neutral lipid accumulation in Chlorella ellipsoidea and Chlorococcum infusionum with flow cytometry and confocal microscopy was established by employing different solvents and a lipophilic dye, Nile red. Seven different organic solvents, acetic acid, dimethyl sulfoxide (DMSO), acetone, methanol, ethanol, n-hexane, and chloroform at different concentrations ranging from 0 to 80% (v/v) were tested. The fluorescence signal for neutral lipids was collected with a 586/42 emission filter (PE-A) and the maximum fluorescence intensity (% grandparent) was measured as 74.01 ± 4.82% for Chlorella and 70.1 ± 5.52% for Chlorococcum at 30% acetic acid (v/v). The statistical analysis of Nile red-stained cells showed a high coefficient of variation (CV), standard deviation (SD), mean, and median values in the acetic acid-based staining method, followed by DMSO, n-hexane and chloroform. Confocal microscopy revealed a high rate of accumulation of cytosolic neutral lipids when stained with Nile red and other organic solvents. Higher lipid accumulation in Fesupplemented conditions was also detected and a maximum lipid content of 57.36 ± 0.41% (4-fold) in Chlorella and 48.20 ± 0.43% (4-fold) in Chlorococcum were measured at 0.001 g/L of ferrous sulfate (FeSO₄). High fluorescence intensity (75.16 ± 0.24% in Chlorella and 72.24 ± 1.07% in Chlorococcum) in Fe-treated cells confirmed the efficiency of the staining procedure.     

The absence of cyclin-dependent protein kinase Pho85 affects stability of mitochondrial DNA in yeast <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis>

The cyclin-dependent protein kinase Pho85 is involved in the regulation of phosphate metabolism in yeast Saccharomyces cerevisiae. Mutations in the PHO85 gene lead to constitutive synthesis of Pho5 acid phosphatase, a delay in cell growth on media containing nonfermentable carbon sources, and other pleiotropic effects. In this work, it was shown that the accumulation of respiratory incompetent cells occurs with high frequency in strains carrying pho85 mutations as early as during the first cell divisions, and the number of these cells at the early logarithmic growth phase of the culture promptly reaches virtually 100%. Cytological analysis revealed a high accumulation rate of [rho⁰] cells in the background of gene pho85 that may be related to disturbances in the distribution of mitochondrial nucleoids rather than to changes in morphology of mitochondria and a delay in their transport into the bud. Genetic analysis revealed that secondary mutations pho4, pho81, pho84, and pho87 stabilize nucleoids and prevent the loss of mitochondrial DNA caused by pho85. These results provide an evidence for the influence of intracellular phosphate concentration on the inheritance of mitochondrial nucleoids, but do not exclude the possibility that the occurrence of mutation pho4 in the background of gene pho85 may change the expression level of other genes required for the stabilization of mitochondrial functions.     

A reexamination on the deficiency of riboflavin accumulation in Malpighian tubules in larval translucent mutants of the silkworm, <Emphasis Type="Italic">Bombyx mori</Emphasis>

A variety of insects accumulate high contents of riboflavin (vitamin B₂) in their Malpighian tubules (MTs). Although this process is known to be genetically controlled, the mechanism is not known. In the 1940s and the 1950s, several studies showed that riboflavin contents were low in the MTs of some Bombyx mori (silkworm) mutants with translucent larval skin mutations (e.g., w-3, od, oa, and otm) and that genes responsible for these translucent mutations also affected riboflavin accumulation in the MTs. Since the 2000s, it has been shown that the w-3 gene encodes an ABC transporter, whereas genes responsible for od, oa, and otm mutations encode for the biogenesis of lysosome-related organelles. These findings suggest that some genes of ABC transporters and biogenesis of lysosome-related organelles may control the accumulation of riboflavin in MTs. Therefore, we reexamined the effects that translucent mutations have on the accumulation of riboflavin in MTs by using the translucent and wild-type segregants in mutant strains to measure the specific effect that each gene has on riboflavin accumulation (independent of genomic background). We used nine translucent mutations (w-3^oe, oa, od, otm, Obs, oy, or, oh, and obt) even though the genes responsible for some of these mutations (Obs, oy, or, oh, and obt) have not yet been isolated. Through observation of larval MTs and measurements of riboflavin content using high-performance liquid chromatography, we found that the oa, od, otm, and or mutations were responsible for low contents of riboflavin in MTs, whereas the Obs and oy mutations did not affect riboflavin accumulation. This indicates that the molecular mechanism for riboflavin accumulation is similar but somewhat different than the mechanism responsible for uric acid accumulation in epidermal cells. We found that the genes responsible for oa, od, and otm mutations were consistent with those already established for uric acid accumulation in larval epidermis. This suggests that these three genes control riboflavin accumulation in MTs through a mechanism similar to that of uric acid accumulation, although we do not yet know why the or mutation also controls riboflavin accumulation.     

Diversity and characterization of cultivable oleaginous yeasts isolated from mangrove forests

A total of 198 yeasts were isolated from 140 samples collected from 7 mangrove forests in 4 provinces of Thailand, and were found to belong to 30 genera, 45 described species and at least 12 undescribed species based on their 26S rRNA (D1/D2 domain) gene sequence. The most prevalent species was Candida tropicalis, followed by Candida pseudolambica and Rhodosporidium paludigena. Lipid accumulation, as determined by Nile red staining, of the isolated yeasts revealed that 69 and 18 strains were positive and strongly positive, respectively, while quantitative analysis of the intracellular lipid accumulated in the latter indicated that 10 of these strains, Pseudozyma tsukubaensis (YWT7-2 and YWT7-3), Rhodotorula sphaerocarpa (YWW6-1 and SFL14-1SF), Saitozyma podzolica (YWT1-1, NS3-3 and NS10-2), Prototheca zopfii var. hydrocarbonea OMS6-1 and Prototheca sp. (YMTW3-1 and YMTS5-2), were oleaginous. In this study we found that under nitrogen depletion condition (155 C/N ratio) Pseudozyma tsukubaensis YWT7-2 accumulated the highest level of intracellular lipid at 32.4% (w/w, dry cell weight), with a broadly similar fatty acid composition to that in palm oil.     

Identification and mapping of resistance to stem rust in the European winter wheat cultivars Spark and Rialto

A mapping population of 126 doubled haploid (DH) lines derived from a cross between the English winter wheat cultivars Spark and Rialto was evaluated for response to Puccinia graminis f. sp. tritici in the greenhouse and in artificially inoculated field plots at two locations over 3 years (2011, 2012 and 2013). Genetic analysis indicated the involvement of two seedling genes (Sr5 and Sr31, contributed by Rialto) and three adult plant resistance genes. QTL analyses of field data showed the involvement of three consistent effects QTL on chromosome arms 1BS (contributed by Rialto), and 3BS and chromosome 5A (contributed by Spark) in the observed resistance to stem rust. These QTLs explained average phenotypic variation of 78.5, 9.0 and 5.9 %, respectively. With the presence of virulence for Sr5 and absence of Sr31 virulence in the field, the QTL detected on 1BS (QSr.sun-1BS) was attributed to the major seedling resistance gene Sr31. The QTL located on chromosome arm 3BS (QSr.sun-3BS) was closely associated with SSR marker gwm1034, and the QTL detected on 5A (QSr.sun-5A) was closely linked with SSR marker gwm443. DH lines carrying the combination of QSr.sun-3BS and QSr.sun-5A exhibited lower stem rust responses indicating the additive effects of the two APR genes in reducing disease severity. The markers identified in this study can be useful in pyramiding these QTLs with other major or minor genes and marker assisted selection for stem rust resistance in wheat.     

Intestinal enterobacteria of the hibernating <Emphasis Type="Italic">Apis mellifera mellifera</Emphasis> L. bees

Dynamics of enterobacteria of normal intestinal microflora was studied in Apis mellifera mellifera L. bees hibernating under snow in the Western Urals. The cell numbers (N) of the predominant species Klebsiella oxytoca increased from 10-10⁶ CFU/bee in November 2004 to 10⁴-10⁷ CFU/bee in March 2005; its frequency of occurrence (P) increased from 92 to 100%. Increase of Providencia rettgeri (11.2004: N up to 10⁶, P 25%; 03.2005: N 10²-10⁶, P 80%) was accompanied by the substitution of Morganella morganii (11.2004: N up to 10⁶, P 25%) with Proteus vulgaris (03.2005: N up to 10⁵, P 8%). By spring, Hafnia alvei and Citrobacter sp., which are pathogenic to bees, disappeared (11.2004: N up to 10⁵, P 13 and 10%, respectively). Endophytic species Pantoea agglomerans, Leclecria sp., and other representatives of the “Enterobacter agglomerans” group were present in November and after the first emergence in spring (N up to 10⁵; November: P 15%; April: P 23%). In April, the number of enterobacteria decreased to 10⁵, and P. rettgeri became the predominant species (P 54%) instead of K. oxytoca (P 43%).     

Identification and expression analysis of the <Emphasis Type="Italic">Eucommia ulmoides</Emphasis> farnesyl diphosphate synthase gene family to reveal the key gene involved in rubber biosynthesis

Eucommia ulmoides Oliver is rich in trans-polyisoprene rubber (Eu-Rubber), a high-molecular mass polymer of isoprene units with a trans-configuration. Farnesyl diphosphate (FPP) synthase (FPS) is a key enzyme, which involved in the production of important precursors of different terpenoids. In this study, we cloned and characterized five novel FPS genes from E. ulmoides. The full-length synthases were named EuFPS1-5 and their deduced amino acid sequences exhibited high homology to those from other plant isoforms. EuFPS1 and EuFPS4 were observed to be highly expressed in leaves, EuFPS2 and EuFPS3 were present at low levels in leaves and fruit throughout the plant development, and EuFPS5 was highly expressed exclusively in young fruit. Expression of EuFPS5 correlated with the accumulation rate of Eu-Rubber and might be responsible for it. This study is expected to enhance our understanding of the role of EuFPSs in biosynthesis and regulation of useful secondary metabolites in E. ulmoides.     

Reliability of the search for 19 common mutations in the <Emphasis Type="Italic">CFTR</Emphasis> gene in Russian cystic fibrosis patients and the calculated frequency of the disease in Russian Federation

A study of Russian cystic fibrosis (CF) patient DNA was conducted to assess the incidence frequency of 19 mutations, namely CFTRdele2,3(21kb), F508del, I507del, 1677delTA, 2143delT, 2184insA, 394delTT, 3821delT, L138ins, 604insA, 3944delGT, G542X, W1282X, N1303K, R334W, and 3849 + 10kbC > T, S1196X, 621 + 1g > t, and E92K of the CFTR gene. We also sought to determine the estimated CF frequency in Russian Federation. In addition, we determined the total information content of the approach for 19 common mutations registration in the CFTR gene, 84.6%, and the allelic frequencies of the examined mutations: three mutations were observed with a frequency exceeding 5% (F508del, 53.98%, E92K, 6.47%, CFTRdele2,3(21kb), 5.35%); other mutations were observed with frequencies ranging from 0.13 to 3.0%. The CF population carrier frequency was 1 in 38 subjects, while the predicted CF frequency was 1 in 5776 newborns.     

Mapping of novel salt tolerance QTL in an Excalibur × Kukri doubled haploid wheat population

Key message

Novel QTL for salinity tolerance traits have been detected using non-destructive and destructive phenotyping in bread wheat and were shown to be linked to improvements in yield in saline fields.

Abstract

Soil salinity is a major limitation to cereal production. Breeding new salt-tolerant cultivars has the potential to improve cereal crop yields. In this study, a doubled haploid bread wheat mapping population, derived from the bi-parental cross of Excalibur?×?Kukri, was grown in a glasshouse under control and salinity treatments and evaluated using high-throughput non-destructive imaging technology. Quantitative trait locus (QTL) analysis of this population detected multiple QTL under salt and control treatments. Of these, six QTL were detected in the salt treatment including one for maintenance of shoot growth under salinity (QG_(1–5).asl-7A), one for leaf Na⁺ exclusion (QNa.asl-7A) and four for leaf K⁺ accumulation (QK.asl-2B.1, QK.asl-2B.2, QK.asl-5A and QK:Na.asl-6A). The beneficial allele for QG_(1–5).asl-7A (the maintenance of shoot growth under salinity) was present in six out of 44 mainly Australian bread and durum wheat cultivars. The effect of each QTL allele on grain yield was tested in a range of salinity concentrations at three field sites across 2 years. In six out of nine field trials with different levels of salinity stress, lines with alleles for Na⁺ exclusion and/or K⁺ maintenance at three QTL (QNa.asl-7A, QK.asl-2B.2 and QK:Na.asl-6A) excluded more Na⁺ or accumulated more K⁺ compared to lines without these alleles. Importantly, the QK.asl-2B.2 allele for higher K⁺ accumulation was found to be associated with higher grain yield at all field sites. Several alleles at other QTL were associated with higher grain yields at selected field sites.

     

Identification of genes showing differential expression profile associated with growth rate in skeletal muscle tissue of Landrace weanling pig

Suppression subtractive hybridization was used to identify genes showing differential expression profile associated with growth rate in skeletal muscle tissue of Landrace weanling pig. Two subtracted cDNA populations were generated from musculus longissimus muscle tissues of selected pigs with extreme expected breeding values at the age of 100 kg. Three upregulated genes (EEF1A2, TSG101 and TTN) and six downregulated genes (ATP5B, ATP5C1, COQ3, HADHA, MYH1 and MYH7) in pig with genetic propensity for higher growth rate were identified by sequence analysis of 12 differentially expressed clones selected by differential screening following the generation of the subtracted cDNA population. Real-time PCR analysis confirmed difference in expression profiles of the identified genes in musculus longissimus muscle tissues between the two Landrace weanling pig groups with divergent genetic propensity for growth rate. Further, differential expression of the identified genes except for the TTN was validated by Western blot analysis. Additionally, the eight genes other than the ATP5C1 co-localized with the same chromosomal positions as QTLs that have been previously identified for growth rate traits. Finally, the changes of expression predicted from gene function suggested association of upregulation of expression of the EEF1A2, TSG101 and TTN genes and downregulation of the ATP5B, ATP5C1, COQ3, HADHA, MYH1 and MYH7 gene expression with increased growth rate. The identified genes will provide an important insight in understanding of the molecular mechanism underlying growth rate in Landrace pig breed.