Association of endothelin-1 gene polymorphisms with essential hypertension in a Chinese population.

Endothelin-1 (ET-1) is the most potent endogenous vasoconstrictor and is involved in several vascular disorders such as hypertension. Its strong interaction with other vasoactive hormone systems suggests that the ET-1 gene (EDN1) is a potential candidate molecule that influences the risk of developing hypertension. Recently, two single nucleotide polymorphisms in EDN1 have been reported to be associated with hypertension: Lys198Asn and 3A/4A (-134delA) located in the 5'-untranslated region. To determine the association of these two polymorphisms with hypertension, we genotyped patients and controls (N = 537) and compared the allele and genotype frequencies between groups. There was no significant difference in the genotype frequencies of these two polymorphisms between healthy controls and hypertension patients. Although previous reports have revealed a significant interaction between the END1 Lys198Asn (G/T) polymorphism and body mass index in association with hypertension, no such relationship was observed in the present study. Further, we compared blood pressure among hypertensive subjects and observed that neither systolic nor diastolic blood pressure was significantly associated with variations in the genotypes of the two single nucleotide polymorphisms. In summary, these two END1 polymorphisms do not appear to affect the development of hypertension in the Chinese population.

Attenuation of renal ischemic reperfusion injury by salvianolic acid B via suppressing oxidative stress and inflammation through PI3K/Akt signaling pathway.

Salvianolic acid B (SAB) is one the major phytocomponents of Radix Salvia miltiorrhiza and exhibit numerous health promoting properties. The objective of the current study was to examine whether SAB exerts a renoprotective effect by attenuating oxidative stress and inflammatory response through activating phosphatidylinositol 3-kinase/serine-threonine kinase B (PI3K/Akt) signaling pathway in a renal ischemic reperfusion rat model. Forty Sprague-Dawley male rats (250-300 g) were obtained and split into four groups with ten rats in each group. The right kidney of all rats was removed (nephrectomy). The rats of the Control group received only saline (occlusion) and served as a sham control group, whereas rats subjected to ischemic reperfusion (IR) insult by clamping the left renal artery served as a postitive control group. The other 2 groups of rats were pretreated with SAB (20 and 40 mg·kg-1·day-1) for 7 days prior IR induction and served as treatment groups (SAB 20+IR; SAB 40+IR). Renal markers creatinine (Cr) and blood urea nitrogen (BUN) were significantly lower in the groups that received SAB. Pretreatment with SAB appears to attenuate oxidative stress by suppressing the production of lipid peroxidation products like malondialdehyde as well as elevating antioxidant activity. The concentration of inflammatory markers and neutrophil infiltration (myeloperoxidase) were significantly decreased. Meanwhile, PI3K protein expression and pAkt/Akt ratio were significantly upregulated upon supplementation with SAB, indicating its renoprotective activity. Taken together, these results indicate that SAB can therapeutically alleviate oxidative stress and inflammatory process via modulating PI3K/Akt signaling pathway and probably ameliorate renal function and thus act as a renoprotective agent.

Targeting effect of microRNA on CD133 and its impact analysis on proliferation and invasion of glioma cells.

MiR-200b, a member of the microRNA-200 family, has been identified to be capable of suppressing glioma cell growth through targeting CREB1 or CD133. However, whether miR-200b affects the biological behavior (proliferation, invasion, and migration) of glioma cells is poorly understood. The aim of this study was to evaluate the effect of miR-200b on the biological behavior of glioma cells in vitro. MiRNA-200b mimics, miRNA-200b inhibitor, and mimic control were transfected into conventionally cultured glioma U251 cells, followed by measuring the expression of miR-200b and CD133 in transfected cells by RT-PCR; effect of miR-200b on CD133 mRNA 3'-UTR luciferase activity by luciferase reporter assay; proliferation activity of transfected U251 cells by MTT method; and changes in U251 cell invasion and migration by Transwell method after transfection. Compared to that in the miRNA-200b inhibitor, mimic control, and blank control groups, miRNA-200b expression was significantly increased and CD133 mRNA expression was significantly decreased in the mimic miRNA-200b group in a time-dependent manner (P < 0.05). Meanwhile, dual luciferase reporter assay showed that miR-200b could inhibit CD133 activity through binding to the 3'-UTR of CD133 mRNA (P < 0.05). Furthermore, the proliferation activity and invasion and migration abilities of U251 cells transfected with miRNA-200b mimic were significantly decreased (P < 0.05). In conclusion, overexpression of miR-200b inhibited the proliferation, invasion, and migration of glioma cells possibly through targeting CD133.

Inhibition of invasion and migration of prostate cancer cells by miRNA-509-5p via targeting MDM2.

Prostate cancer is a common malignancy of the male reproductive-urinary system. MDM2 is an oncogene, whose expression can be regulated by microRNA (miRNA). The present study investigated the expression and correlation of miRNA-509-5p and MDM2 to determine the mechanism of their function in invasion and migration of prostate cancer cells. RT-PCR was performed to detect the expression of miRNA-509-5p and MDM2 in tumor, tumor-adjacent, and normal tissues, obtained from prostate cancer patients, using the HGC-27 cell line as an in vitro model. Cultured HGC-27 cells were transfected with miRNA-509-5p mimics, miRNA-509-5p inhibitor, and mimic control. Expression levels of miRNA-509-5p and MDM2 were quantified by RT-PCR. Cell proliferation and invasion/migration were examined by the MTT and transwell assays, respectively. MiRNA-509-5p was significantly down-regulated in prostate cancer cells exhibiting high MDM2 mRNA levels. MiRNA mimic transfection elevated miRNA levels and suppressed MDM2 expression. With prolonged incubation time, the proliferation ratio and OD values of miRNA-509-5p mimic transfected cells decreased, along with decrease in cell migration and invasion. These results suggested that miRNA-509-5p negatively regulates MDM2 expression via targeting the 3'-UTR of genes. As a novel tumor suppressor, miRNA-509-5p in prostate cancer HGC-27 cells can suppress MDM2 expression and inhibit cell proliferation, invasion, and migration. Therefore, miRNA-509-5p could be used as a novel therapeutic agent in the treatment of prostate cancer.

Characterizing and marker-assisting a novel chili pepper (Capsicum annuum L.) yellow bud mutant with cytoplasmic male sterility.

Cytoplasmic male sterility (CMS) in pepper is a better way to produce hybrid seeds compared to manual production. We used the two sequence characterized amplified region (SCAR) markers (CRF-SCAR and CMS-SCAR130) in CMS pepper, to identify the genotype. We assembled two CMS yellow bud mutants (YBM; YBM12-A and YBM12-B). This mutation in leaf color is controlled by a single dominant nuclear gene. The aim was to create a new hybrid seed production method that reduces the costs and increases F1 hybrid seed purity. The results suggest that the CRF-SCAR and CMS-SCAR130 markers can be used together in multiple generations to screen for restorer or maintainer genes. We found the marker linked to the restorer gene (Rf) in the C-line and F1 hybrids, as well as partially in the F2 generation, whereas it was not found in the sterile YBM12-A or the maintainer line YBM12-B. In the F2 population, sterility and fertility segregated at a 3:1 ratio based on the CRF-SCAR marker. A 130 bp fragment was produced in the YBM12-A, F1, and F2 populations, suggesting that these lines contained sterile cytoplasm. A 140 bp fragment present in the YBM12-B and C-line indicated that these lines contained normal cytoplasm. In addition, we identified some morphological characters distinguishing sterile and fertile buds and flowers that may be linked to the sterility gene. If more restorer lines are identified, CMS expressing the YBM trait can be used in hybrid seed production.

Effects of sodium lactate Ringer's injection on transfection of human protein kinase C-α antisense oligonucleotide in A549 lung cancer cells.

In the present study, we evaluated the effects of four solutions [Dulbecco's modified Eagle's medium (DMEM), sodium lactate Ringer's injection (SLRI), phosphate-buffered saline (PBS), and NaCl] on the transfection of the human protein kinase C-a antisense oligonucleotide (PKC-a ASO) aprinocarsen in human lung carcinoma A549 cells. Specifically, SLRI, DMEM, PBS, or NaCl were used as the growth solutions for A549 cells, and OPTI-MEM was used as the PKC-a ASO diluent for transfection. Additionally, SLRI, DMEM, PBS, or NaCl were used as both the growth solutions and diluents for transfection. The cell viability and transfection efficiency were determined. The results demonstrated that when SLRI was used as either the growth solution or both the growth solution and diluent for aprinocarsen transfection in A549 cells, the effects were close to the best effects observed with DMEM as the growth solution and OPTI-MEM as the diluent, which supported the transfection of aprinocarsen into the cells. Moreover, SLRI resulted in higher transfection efficiency than those of PBS and NaCl. In in vitro experiments, aprinocarsen effectively induced apoptosis in A549 cells. In conclusion, SLRI may replace PBS or NaCl in clinical trials as a transfection solution readily accepted by the human body. To our knowledge, this is the first report demonstrating the use of SLRI as a transfection solution in lung-cancer cell lines.

Antisense expression of Gossypium hirsutum UDP-glucuronate decarboxylase in Arabidopsis leads to changes in cell wall components.

UDP-glucuronate decarboxylase (UDP-xylose synthase; UXS, EC 4.1.1.35) is an essential enzyme of the non-cellulosic polysaccharide biosynthetic pathway. In the present study, using transient expression of fluorescently labeled Gossypium hirsutum UXS (GhUXS3) protein in onion epidermal cells, we observed that this protein was distributed in the cytoplasm. The GhUXS3 cDNA of cotton was expressed in an antisense orientation in Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation. Homozygous plants showing down-regulation of UXS were analyzed with northern blots. Compared to the untransformed control, transgenic plant showed shorter roots, earlier blossom formation, and delayed senescence. Biochemical analysis indicated that levels of rhamnose, mannose, galactose, glucose, xylose, and cellulose were reduced in some of the down-regulated antisense plants. These results suggest that GhUXS3 regulates the conversion of non-cellulosic polysaccharides and modulates their composition in plant cell walls. We also discuss a possible cellular function for GhUXS in determining the quality of cotton fibers.

Translation of foot-and-mouth disease virus RNA: factors influencing alternative AUG selection.

The mechanism of alternative AUG usage in foot-and-mouth disease virus is not completely understood. Using simple computational approaches, we evaluated the contributions of overall codon bias, quantitative codon bias, and %GC of the region between the two alternative AUGs, Region-La, as well as the nucleotide bias of the sequence context flanking each AUG with respect to translation initiation efficiency. For all serotypes of this virus, we found that only a small component of the effect of RNA secondary structure on ribosome scanning was due to the low %GC of Region-La. In addition, we found that the nucleotide bias of the context from position -4 to +6 flanking the AUG(2nd) had a negative correlation with the overall codon bias, and that a strong purine bias existed in this AUG(2nd)context. However, the quantitative codon bias of Region-La was seen to be significantly lower than that of Region-Lb (the sequence following AUG(2nd)) in all serotypes except SAT 1-3. Taken together, our results suggest that the low codon bias of Region-La might impair the translation initiation efficiency at the AUG(1st) in all serotypes except SAT 1-3, and the specific AUG(2nd) context might be used as a strong signal to initiate translation from the AUG(2nd) in all serotypes.

Overexpression of EsMcsu1 from the halophytic plant Eutrema salsugineum promotes abscisic acid biosynthesis and increases drought resistance in alfalfa (Medicago sativa L.).

The stress phytohormone abscisic acid (ABA) plays pivotal roles in plants' adaptive responses to adverse environments. Molybdenum cofactor sulfurases influence aldehyde oxidase activity and ABA biosynthesis. In this study, we isolated a novel EsMcsu1 gene encoding a molybdenum cofactor sulfurase from Eutrema salsugineum. EsMcus1 transcriptional patterns varied between organs, and its expression was significantly upregulated by abiotic stress or ABA treatment. Alfalfa plants that overexpressed EsMcsu1 had a higher ABA content than wild-type (WT) plants under drought stress conditions. Furthermore, levels of reactive oxygen species (ROS), ion leakage, and malondialdehyde were lower in the transgenic plants than in the WT plants after drought treatment, suggesting that the transgenic plants experienced less ROS-mediated damage. However, the expression of several stress-responsive genes, antioxidant enzyme activity, and osmolyte (proline and total soluble sugar) levels in the transgenic plants were higher than those in the WT plants after drought treatment. Therefore, EsMcsu1 overexpression improved drought tolerance in alfalfa plants by activating a series of ABA-mediated stress responses.

Investigations on the genomic diversity of OXA from isolated Acinetobacter baumannii.

We distinguished the four OXA-type carbapenemase subgroup alleles present in 120 strains of Acinetobacter baumannii by using polymerase chain reaction (PCR) and investigated the distributions of the OXA subgroups in clinically isolated samples. Amplification of the OXA genes blaOXA-23, blaOXA-24, blaOXA-51, and blaOXA-58 was performed by multiplex PCR. Antibiotics susceptibility test was conducted for determine the sensitivity of the A. baumannii to clinical common used antibiotics by Kirby-Bauer method. Results revealed that 46 (51.69%) of the samples were positive for only the blaOXA51 gene and 41 (46.07%) were positive for both the blaOXA51 and blaOXA58 genes in the 89 isolates of A. baumannii. Among these, 45 were carbapenem-resistant and 44 carbapenem-sensitive. Strains containing either blaOXA51 or blaOXA58 showed resistance or sensitivity to carbapenems, respectively. A. baumannii isolated from intensive care units showed significantly higher resistance rate to Cefepime, Piperacillin-tazobactam, Amikacin, Ceftazidime, Cefotaxime, Sulfamethoxazole-trimethoprim, and Gentamicin than those isolated from other departments (P < 0.05). In conclusion, we found that the presence of blaOXA-51 and blaOXA-58 appears to convey a mechanism of resistance or sensitivity to carbapenems, respectively, in A. baumannii clinical isolates.

Mapping quantitative trait loci for nitrogen uptake and utilization efficiency in rice (Oryza sativa L.) at different nitrogen fertilizer levels.

Genetic improvement is the fundamental basis for improving nitrogen-use efficiency. A better understanding of genetic factors controlling nitrogen uptake and utilization is required for crop genetic improvement. In this study, we identified the quantitative trait loci (QTLs) associated with traits of nitrogen uptake and utilization by using the single-sequence repeat marker method and a recombinant inbred line (RIL) population derived from a super hybrid Xieyou9308. All the traits investigated were inherited quantitatively by continuous variation and showed normal distribution in phenotype with transgressive segregation in the RIL population. Most of the traits were significantly correlated with each other except for nitrogen absorption ability (NAA) with nitrogen harvest index (NHI) and NHI with agricultural nitrogen-absorption efficiency (ANAE). At logarithmic odds value of 2.3, total 13 candidate QTLs, including 4 for NAA, 2 for NHI, 2 for physiological nitrogen-use efficiency, 1 for agricultural nitrogen-use efficiency (ANUE), and 4 for ANAE, were detected and mapped on chromosomes 2, 3, 4, 5, 8, 9, 10, and 12. Significant pleiotropic effect or neighboring expression of QTLs was observed among traits. At position 64.8 cM on chromosome 4 near the marker RM5757, there was a QTL cluster of NAA, ANUE, and ANAE, and at chromosome 5 near the marker RM5968, there was a QTL cluster of NAA and ANUE. The QTL clusters might provide partial explanation and genetic mechanism for the observed correlations between nitrogen uptake and utilization efficiency traits and might form a basis for future breeding programs.

Transcriptome sequencing and analysis of the coconut leaf beetle, Brontispa longissima.

The coconut leaf beetle, Brontispa longissima, is a destructive pest of palm plants. Although its ecological and biological characteristics are well understood, its genetic information remains largely unknown. To advance our understanding of its molecular ba-sis of biology and ecology, we sequenced and analyzed its whole transcriptome by using high-throughput Illumina paired-end sequencing technology. Approximately 8.08 Gb of clean reads were generated in a single run, which were assembled by using Trinity into 41,652 unigenes with an average length of 932 bp. By sequence similarity searches for known proteins, 23,077 (55.4%) unigenes were annotated by BLASTx searches against the NCBI non-redundant protein database. Of the unigenes assembled, 18,153 and 13,733 were assigned to Gene Ontology and Clusters of Orthologous Groups of proteins, respectively. In addition, 10,415 unigenes were mapped onto 247 pathways using the Kyoto Encyclopedia of Genes and Genomes Pathway database. These transcriptomic resources will facilitate gene identification and elucidate the molecular mechanisms of biological and ecological aspects under-lying this palm pest, in order to design a new control strategy.

Postpartum pelvic floor function performance after two different modes of delivery.

This study investigated the incidences of urinary incontinence and pelvic organ prolapse as well as pelvic floor muscle strength after cesarean section and vaginal delivery. From June 2010 to July 2011, 149 puerpera in Shenzhen Hospital, Peking University, were divided into the cesarean section group (N = 66) and the vaginal delivery group (N = 83). Postpartum urinary incontinence analysis, pelvic examination, and pelvic muscle contraction analysis using the PHENIX neuromuscular therapy instrument were performed to compare urinary incontinence, pelvic organ prolapse, and pelvic floor muscle condition between the 2 groups. The incidences of urinary incontinence in the cesarean and vaginal delivery groups were 9.09% (6/66) and 16.87% (14/83), respectively (P > 0.05); the incidences of pelvic organ prolapse were 53.03% (35/66) and 86.75% (72/83), respectively (P < 0.05). There was no significant difference in pelvic muscle pressure or electrophysiological examination results between the 2 groups (P > 0.05). Hence, cesarean section has a protective effect on early postpartum pelvic organ prolapse, but the delivery modes do not differ significantly with respect to the incidence of postpartum urinary incontinence or pelvic muscle floor muscle strength.

Comparison of integrated traditional Chinese and western medicine therapy on vascular cognitive impairment with no dementia.

The aim of this study was to investigate the clinical effect of western medicine therapy assisted by Ginkgo biloba tablets (GBT) in patients with vascular cognitive impairment with no dementia (VCIND). Eighty patients with VCIND were randomly divided into two groups: the conventional treatment group (control group) and the combined treatment group. The conventional treatment group was provided with anti-platelet aggregation conventional treatment. In this group, 75 mg aspirin was given three times a day for 3 months, whereas the combined treatment group was given 19.2 mg GBT three times a day for 3 months along with conventional anti-platelet aggregation treatment. Montreal cognitive assessment (MoCA) and transcranial Doppler ultrasonography were used to observe changes in cognitive ability and cerebral blood flow in patients with VCIND before and after treatment in the two groups. After 3 months of treatment, the MoCA scores of execution, attention, abstraction, delayed memory, and orientation were significantly increased in the combined treatment group compared with those before treatment and those in the control group after treatment. In addition, the blood flow velocity of the anterior cerebral artery was significantly increased in the combined treatment group. GBT can improve the therapeutic efficacy, cognitive ability, and cerebral blood flow supply of patients with VCIND.

Genetic diversity and classification of Tibetan yak populations based on the mtDNA COIII gene.

To determine the level of genetic diversity and phylogenetic relationships among Tibetan yak populations, the mitochondrial DNA cytochrome c oxidase subunit 3 (COIII) genes of 378 yak individuals from 16 populations were analyzed in this study. The results showed that the length of cytochrome c oxidase subunit 3 gene sequences was 781 bp, with nucleotide frequencies of 29.2, 29.4, 26.1, and 15.2% for T, C, A, and G, respectively. A total of 26 haplotypes were identified, with 69 polymorphic sites, including 11 parsimony-informative sites and 58 single-nucleotide polymorphism sites. No deletions/insertions were found in sequence comparison, indicating that nucleotide mutation types were transitions and transversions. Haplotype and nucleotide diversities were 0.562 and 0.00138, respectively, indicating a high level of genetic diversity in Tibetan yak populations. Phylogenetic relationship analysis indicated that Tibetan yak populations are divided into 2 groups.

IL-8 -251T/A polymorphism is associated with susceptibility to acute pancreatitis.

We conducted a case-control study to clarify the asso-ciations between inflammatory cytokine, including interleukin (IL)-1b, IL-6, IL-8, and IL-10, polymorphisms and risk of acute pancreatitis. Genotyping analyses of IL-1ß+3954 C/T (rs1143634), IL-1ß-511 C/T (rs16944), IL-6 -174 G/C (rs1800795), IL-6 -634 C/G (rs1800796), IL-8 -251T/A (rs4073), IL-10 -1082A/G (rs1800896), and IL-10 -819C/T (rs1800871) were conducted using polymerase chain reaction-restriction fragment length of polymorphism. Unconditional logistic regression analysis was utilized to assess the potential association be-tween genotype frequencies and risk of acute pancreatitis. Multivari-ate regression analyses showed that subjects carrying the IL-8 -251 AA genotype had a significantly increased risk of acute pancreatitis, with an adjusted odds ratio (95% confidence interval) of 1.55 (1.02-2.36). However, we found no significant association between IL-1ß +3954 C/T, IL-1ß -511 C/T, IL-6 -174 G/C, IL-6 -174 G/C, IL-6 -634 C/G, IL-10 -1082A/G, or IL-10 -819C/T polymorphisms and risk of acute pancreatitis. We found that the IL-8 -251T/A polymorphism was associated with a higher susceptibility to acute pancreatitis in a Chinese population.

Y-STR INRA189 polymorphisms in Chinese yak breeds.

To further explore Y-STR INRA189 polymorphisms in the yak, and to determine the genetic differences among yak breeds, genotyping analysis of INRA189 in 102 male yak individuals from three yak breeds in Qinghai Province of China was performed. Genotyping revealed the presence of four alleles, with sizes of 149, 155, 157, and 159 bp, respectively. Of these, the 157-bp allele, which was found with the highest frequency in the three yak breeds, was the dominant allele. Interestingly, the 149-bp allele was only detected in the Gaoyuan breed, and the 159-bp allele was only found in the Huanhu and Datong breeds. Only the 157- and 155-bp alleles were found in all three yak breeds. Taking the three yak breeds as a single population, the frequency of these four alleles was 0.0294, 0.0686, 0.8628, and 0.0392, respectively. The average polymorphism information content in the three yak breeds was 0.2379, indicating that the INRA189 was a low polymorphic Y-STR marker in yak.

Genetic features of a translation initiation system composed of IRES element, nucleotide context surrounding the initiation codon, and translation initiation region of classical swine fever virus RNA.

Nucleotide and codon usage are typically examined to investigate viral evolution. In this study, we analyzed the genetic information of 46 strains of classical swine fever virus (CSFV) RNA, nucleotide usage in the internal ribosome entry site (IRES), the nucleotide context surrounding the initiation codon, and synonymous codon usage in the translation initiation region. Phylogenetic analysis of the IRES element indicated that the genetic diversity of this element is generally similar to the phylogenetic clusters of CSFV genotypes. Nucleotides surrounding the initiation codon of CSFV RNA were generally more stable (ACAUGGCACAUGGAGUUG) compared to the internal AUG in the CSFV coding sequence. The second codon position after the initiation codon was generally selected to be GAG, which has lower tRNA abundance in pigs than its synonymous member (GAA). Regarding the synonymous codon usage bias in the CSFV translation initiation region, some codons showing low tRNA abundance in pigs are more frequently located in the translation initiation region than in the open reading frame of CSFV. Although CSFV, similarly to other RNA viruses, has a high mutation rate in nature, the regulatory features of nucleotide and synonymous codon usage of the IRES element, the nucleotide context surrounding the initiation codon and the translation initiation region in CSFV RNA have been 'branded' in the system of translation initiation to accommodate gene expression mediated by the cap-independent translation mechanism.

Characteristics of synonymous codon usage bias in the beginning region of West Nile virus.

Adaptation in the overall codon usage pattern of West Nile virus (WNV) to that of two hosts was estimated based on the synonymous codon usage value (RSCU). Synonymous codon usage biases for the beginning coding sequence of this virus were also analyzed by calculating the usage fluctuation for each synonymous codon along the target region (the first 270 codon sites of the whole coding sequence of WNV). Adaptation of WNV to Anopheles gambiae regarding the overall codon usage revealed a mixture of synonymous codon usage patterns between this virus and its vector. Regarding the adaptation of WNV to its dead-end host and codon usage, although a mixture of overall codon usage patterns exists, the number of codons with reversed tendency codon usage is lower than that between the virus and its vector. In addition, some codons with low RSCU values for this virus are highly selected in the beginning translation region of WNV, while codons with low RSCU values in this region tend to pair with tRNAs present in low abundance in the host, suggesting that highly selected codons in a specific region in the beginning region of WNV are, to some degree, influenced by the corresponding low tRNA abundance of hosts to regulate the translation speed of the WNV polyprotein.

Genome-wide identification and expression profiling of the fatty acid desaturase gene family in the silkworm, Bombyx mori.

Fatty acid desaturases exist in all living organisms and play important roles in many different biologic processes, such as fatty acid metabolism, lipid biosynthetic processes, and pheromone biosynthetic processes. Using the available silkworm genome sequence, we identified 14 candidate fatty acid desaturase genes. Eleven genes contain 3 conserved histidine cluster motifs and 4 transmembrane domains, but their N-terminal residues exhibit obvious diversity. Phylogenetic analysis revealed that there are 6 groups; Bmdesat1 and Bmdesat5-8 were clustered into group 2, which is involved in Δ11 desaturation activity, and Bmdesat3-4 were grouped in group 1, which is involved in Δ9 desaturation activity. Twelve of the 14 genes have expressed sequence tag evidence. Microarray data and reverse transcription polymerase chain reaction analysis demonstrated that Bmdesat3-4 and Bmdesat10 were expressed from the larval to moth stages and in multiple tissues on day 3 of 5th instar larvae. Bmdesat9, Bmdesat11, and Bmdesat14 were expressed during the pupal and late-embryonic stage, suggesting that they may take part in fatty acid metabolism to provide energy. These results provide some insights into the functions of individual fatty acid desaturases in silkworm.