Identification and validation of housekeeping genes in brains of the desert locust Schistocerca gregaria under different developmental conditions

<p>Abstract</p> <p>Background</p> <p>To obtain reliable quantitative RT-PCR data, normalization relative to stable housekeeping genes is required. However, in practice, expression levels of 'typical' housekeeping genes have been found to vary between tissues and under different experimental conditions. To date, validation studies of reference genes in insects are extremely rare and have never been performed in locusts. In this study, putative housekeeping genes were identified in the desert locust, <it>Schistocerca gregaria </it>and two different software programs (geNorm and Normfinder) were applied to assess the stability of thesegenes.</p> <p>Results</p> <p>We have identified seven orthologs of commonly used housekeeping genes in the desert locust. The selected genes were the orthologs of actin, <it>EF1a, GAPDH, RP49, TubA1, Ubi</it>, and <it>CG13220</it>. By employing real time RT-PCR we have analysed the expression of these housekeeping genes in brain tissue of fifth instar nymphs and adults. In the brain of fifth instar nymphs geNorm indicated <it>Sg-EF1a</it>, <it>Sg-GAPDH </it>and <it>Sg-RP49 </it>as most stable genes, while Normfinder ranked <it>Sg-RP49</it>, <it>Sg-EF1a </it>and <it>Sg-ACT </it>as most suitable candidates for normalization. The best normalization candidates for gene expression studies in the brains of adult locusts were <it>Sg-EF1a, Sg-GAPDH </it>and <it>Sg-Ubi </it>according to geNorm, while Normfinder determined <it>Sg-GAPDH</it>, <it>Sg-Ubi </it>and <it>Sg-ACT </it>as the most stable housekeeping genes.</p> <p>Conclusion</p> <p>To perform transcript profiling studies on brains of the desert locust, the use of <it>Sg-RP49</it>, <it>Sg-EF1a </it>and <it>Sg-ACT </it>as reference genes is proposed for studies of fifth instar nymphs. In experiments with adult brains, however, the most preferred reference genes were <it>Sg-GAPDH</it>, <it>Sg-Ubi </it>and <it>Sg-EF1a</it>. These data will facilitate transcript profiling studies in desert locusts and provide a good starting point for the initial selection of genes for validation studies in other insects.</p

An inverse association between the Mediterranean diet and bladder cancer risk: a pooled analysis of 13 cohort studies

The role of diet in bladder carcinogenesis has yet to be established. To date most studies have investigated dietary components individually, rather than as dietary patterns, which may provide stronger evidence for any influence of diet on bladder carcinogenesis. The Mediterranean diet has been associated with many health benefits, but few studies have investigated its association with bladder cancer risk.Peer reviewe

Transcriptome Analysis of the Desert Locust Central Nervous System: Production and Annotation of a Schistocerca gregaria EST Database

) displays a fascinating type of phenotypic plasticity, designated as ‘phase polyphenism’. Depending on environmental conditions, one genome can be translated into two highly divergent phenotypes, termed the solitarious and gregarious (swarming) phase. Although many of the underlying molecular events remain elusive, the central nervous system (CNS) is expected to play a crucial role in the phase transition process. Locusts have also proven to be interesting model organisms in a physiological and neurobiological research context. However, molecular studies in locusts are hampered by the fact that genome/transcriptome sequence information available for this branch of insects is still limited. EST information is highly complementary to the existing orthopteran transcriptomic data. Since many novel transcripts encode neuronal signaling and signal transduction components, this paper includes an overview of these sequences. Furthermore, several transcripts being differentially represented in solitarious and gregarious locusts were retrieved from this EST database. The findings highlight the involvement of the CNS in the phase transition process and indicate that this novel annotated database may also add to the emerging knowledge of concomitant neuronal signaling and neuroplasticity events. EST data constitute an important new source of information that will be instrumental in further unraveling the molecular principles of phase polyphenism, in further establishing locusts as valuable research model organisms and in molecular evolutionary and comparative entomology

Global variations in diabetes mellitus based on fasting glucose and haemogloblin A1c

Fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) are both used to diagnose diabetes, but may identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening had elevated FPG, HbA1c, or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardised proportion of diabetes that was previously undiagnosed, and detected in survey screening, ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the agestandardised proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global gap in diabetes diagnosis and surveillance.peer-reviewe

Endocrine Control of Reproduction, Insects

edition: 2ndstatus: publishe

Immune-induced angiotensin-converting enzyme assures the appearance of complementary peptides in Locusta migratoria for fine-tuning the innate immune response by inhibiting immune-activated phenoloxidase

status: publishe

Adipokinetic hormone receptor as regulator of energy use in the anutogenous fly, Sarcophaga crasipalpis,

status: publishe

Development of primary cell cultures using hemocytes and phagocytic tissue cells of Locusta migratoria: an application for locust immunity studies

Insect cell cultures played central roles in unraveling many insect physiological and immunological processes. Regardless, despite imminent needs, insect cell lines were developed primarily from Dipteran and Lepidopteran orders, leaving many important insects such as Orthopteran locusts under-represented. Besides the lack of cell lines, the slow progress in development of in vitro techniques is attributed to poor communications between different laboratories regarding optimized primary cell cultures. Therefore, we report here about methods developed for primary cell culture of Locusta migratoria hemocyte and phagocytic tissue cells by which we could maintain viable hemocytes in vitro for over 5 d and phagocytic tissue cells for over 12 d. 2-Mercaptoethanol and phenyl-thiourea supplements in Grace's medium together with addition of fetal bovine serum 30 min after cell seeding resulted in a successful setup of the primary cell cultures and a week-long survival of the hemocytes and phagocytic tissue cells in vitro.status: publishe

Pharmacological regulation of digestion in the anautogenous flesh fly, Sarcophaga crassipalpis, by simple injection of 6-hydroxydopamine

Female anautogenous Sarcophaga flesh flies need a protein meal to start large-scale yolk polypeptides (YPs) production and oocyte maturation. Protein meal rapidly elicits a brain-dependent increase in midgut proteolytic activity. Trypsin and chymotrypsin together represent over 80% of protease activity in liver-fed flies. Abdominal injection of 6-hydroxydopamine (6-OHDA) dose-dependently prohibits this increase in proteolytic activity at translational level in a similar way as post liver feeding decapitation. Delayed injection of 6-OHDA later than 6 h post liver meal has no effect. In flesh flies, chemical decapitation by 6-OHDA, by interrupting the brain-gut dopaminergic signaling, can be used as tool for the controlled inhibition of midgut proteolytic activity and subsequent ovarial development. Inhibition of ovarial development is probably indirect due to a deficit in circulating amino acids needed for YPs synthesis.status: publishe

Similarities in vitellogenin and control of vitellogenin synthesis within the genera sarcophaga, calliphora, phormia and lucilia (diptera)

1. 1. The major yolk polypeptides from the different species are identified by SDS-gradient gel electrophoresis. 2. 2. Vitellogenins of the 4 species have similarities in both minimum number and size of their polypeptides. They also react with antibodies raised against vitellin of Sarcophaga. 3. 3. In males of all species ecdysterone but not the JH analog methoprene induces the yolk polypeptides. 4. 4. In non-protein fed females only ecdysterone is able to replace the triggering effect of the protein meal on vitellogenin synthesis. 5. 5. The inability to stimulate vitellogenin synthesis in vivo by a JH analog is discussed. © 1982.status: publishe