scholarly journals Molecular changes associated with migratory departure from wintering areas in obligate songbird migrants

Author(s):  
Aakansha Sharma ◽  
Devraj Singh ◽  
Priya Gupta ◽  
Sanjay Kumar Bhardwaj ◽  
Inderjeet Kaur ◽  
...  

Daylength regulates the development of spring migratory and subsequent reproductive phenotypes in avian migrants. This study used molecular approaches, and compared mRNA and proteome-wide expressions in captive redheaded buntings that were photostimulated under long days (LD) for 4 days (early stimulated, LD-eS) or for ∼3 weeks until each bird had shown successive 4 nights of Zugunruhe (stimulated, LD-S); controls were maintained under short-days. After ∼3 weeks of LD, photostimulated indices of the migratory preparedness (fattening, weight gain and Zugunruhe) were paralleled with upregulated expression of acc, dgat2 and apoa1 genes in the liver, and of cd36, fabp3 and cpt1 genes in the flight muscle, suggesting an enhanced fatty acids (FAs) synthesis and transport in the LD-S state. Concurrently elevated expression of genes involved in the calcium-ion signaling and transport (camk1 and atp2a2; camk2a in LD-eS instead), cellular stress (hspa8 and sod1, not nos2) and metabolic pathways (apoa1 and sirt1), but not of the genes associated with migratory behaviour (adcyap1 and vps13a), were found in the mediobasal hypothalamus (MBH). Further, the MBH-specific quantitative proteomics revealed that out of 503 annotated proteins, 28 were differentially expressed (LD-eS vs. LD-S: 21 up- and 7 down-regulated) and they enriched five physiological pathways that are associated with fatty acids transport and metabolism. These first comprehensive results on gene and protein expressions suggest that changes in molecular correlates of fatty acids transport and metabolism may aid the decision for migratory departure from wintering areas in obligate songbird migrants.

2016 ◽  
Vol 16 (4) ◽  
pp. 1045-1058 ◽  
Author(s):  
Essa Dirandeh ◽  
Armin Towhidi ◽  
Zarbakht Ansari ◽  
Saeeid Zeinoaldini ◽  
Mehdi Ganjkhanlou

Abstract The objective of this study was to investigate whether dietary supplementation with different polyunsaturated fatty acids (PUFA s) affects expression of genes related to somatotropic axis and the plasma concentrations of insulin, glucose, non-esterified fatty acids (NEFA), beta hydroxyl butyrate acids (BHBA) and insulin-like growth factor 1 (IGF1) and milk fatty acids profile. Right after calving, Holstein cows (n=45) were randomly assigned to one of three diets supplemented with roasted whole soybean as a source of omega-6 PUFA (omega-6, n=15), linseed as a source of omega-3 PUFA (omega-3, n=15) or palm oil (control, n=15). Each cow was in the study over a period of 70 days. Blood samples were collected every two weeks from day 1 to 70 of lactation and plasma concentrations of insulin, glucose, NEFA, BHBA and IGF1 were determined. Liver samples were taken from a subset of 18 cows (6 per diet) at day 70 postpartum and hepatic mRNA level of total growth hormone-receptor 1A (GHR1A), insulin receptor (INSR), IGF1 and insulinlike growth factor binding protein (IGFBP2) was assessed. Experimental diets did not affect milk yield. Plasma glucose and insulin concentrations were greater for omega-3 treatment compared to omega-6 and control treatments. Cows fed diets enriched in omega-3 exhibited greater INSR and GHR1A mRNA expression, and a tendency for greater IGF1 mRNA expression in the liver compared to omega-6 and control cows. Plasma IGF1 concentration was significantly higher in omega-3 treatment compared with omega-6 and control treatments. Results of this study suggest that feeding omega-3 PUFA s during early postpartum couples with the somatotropic axis, leading to an increase in plasma IGF1 concentration in dairy cows.


1995 ◽  
Vol 311 (1) ◽  
pp. 167-173 ◽  
Author(s):  
A J Bennett ◽  
M A Billett ◽  
A M Salter ◽  
E H Mangiapane ◽  
J S Bruce ◽  
...  

Different dietary fatty acids exert specific effects on plasma lipids but the mechanism by which this occurs is unknown. Hamsters were fed on low-cholesterol diets containing triacylglycerols enriched in specific saturated fatty acids, and effects on plasma lipids and the expression of genes involved in hepatic lipoprotein metabolism were measured. Trimyristin and tripalmitin caused significant rises in low-density lipoprotein (LDL) cholesterol which were accompanied by significant reductions in hepatic LDL receptor mRNA levels. Tripalmitin also increased hepatic expression of the apolipoprotein B gene, implying an increased production of LDL via very-low-density lipoprotein (VLDL) and decreased removal of LDL in animals fed this fat. Hepatic levels of 3-hydroxy-3-methylglutaryl-CoA reductase mRNA did not vary significantly between the groups. Compared with triolein, tristearin had little effect on hepatic gene expression or total plasma cholesterol. However, it caused a marked decrease in VLDL cholesterol and a rise in LDL cholesterol such that overall it appeared to be neutral. Lipid analysis suggested a rapid desaturation of much of the dietary stearate. The differential changes in plasma lipids and hepatic mRNA levels induced by specific dietary fats suggests a role for fatty acids or a metabolite thereof in the regulation of the expression of genes involved in lipoprotein metabolism.


2020 ◽  
Vol 28 (4) ◽  
pp. 327-334
Author(s):  
Mahan Mohammadi ◽  
Shiva Irani ◽  
Iman Salahshourifar ◽  
Jalil Hosseini ◽  
Afshin Moradi ◽  
...  

BACKGROUND AND AIM: Prostate cancer is the leading cause of death in many countries. It is important to diagnose the disease in the early stages. Current methods detect the disease with low specificity. Examining the expression of genes responsible for disease and their epigenetic regulators are good tools in this regard. MATERIAL AND METHODS: In this prospective case-control study, 40 Iranian patients with cancer, 40 Iranian patients with prostate hyperplasia, and 40 control samples were examined. After blood sampling from each individual, RNA extraction and cDNA synthesis, GSTP1, HDAC, DNMT3A, and DNMT3B expressions were measured in three understudy groups using specific primers and Real-Time PCR method. RESULTS: A reverse correlation was identified between loss of GSTP1 expression and overexpression of HDAC, DNMT3A, and DNMT3B (P value < 0.0001) with a beneficial pattern of cancer development with high efficiency. The significant decrease of GSTP1 expression in patients in comparison to the healthy controls and the elevated expression levels of the studied epigenetic regulators in PCA and BPH samples indicate the impact of the regulators on GSTP1 expression activity. CONCLUSION: This study showed that the measurement of combined GSTP1 and its epigenetic regulators’ expression could be used as suitable genetic markers for the detection and separation of healthy individuals from prostatic patient groups in the Iranian population. However, a similar study in a larger population of case and control could help us to distinguish between normal, benign, and malignant conditions.


2013 ◽  
Vol 45 (8) ◽  
pp. 321-331 ◽  
Author(s):  
Gretchen A. Meyer ◽  
Simon Schenk ◽  
Richard L. Lieber

In this work, the interaction between the loss of a primary component of the skeletal muscle cytoskeleton, desmin, and two common physiological stressors, acute mechanical injury and aging, were investigated at the transcriptional, protein, and whole muscle levels. The transcriptional response of desmin knockout ( des −/−) plantarflexors to a bout of 50 eccentric contractions (ECCs) showed substantial overlap with the response in wild-type ( wt) muscle. However, changes in the expression of genes involved in muscle response to injury were blunted in adult des −/− muscle compared with wt (fold change with ECC in des −/− and wt, respectively: Mybph, 1.4 and 2.9; Xirp1, 2.2 and 5.7; Csrp3, 1.8 and 4.3), similar to the observed blunted mechanical response (torque drop: des −/− 30.3% and wt 55.5%). Interestingly, in the absence of stressors, des −/− muscle exhibited elevated expression of many these genes compared with wt. The largest transcriptional changes were observed in the interaction between aging and the absence of desmin, including many genes related to slow fiber pathway (Myh7, Myl3, Atp2a2, and Casq2) and insulin sensitivity (Tlr4, Trib3, Pdk3, and Pdk4). Consistent with these transcriptional changes, adult des −/− muscle exhibited a significant fiber type shift from fast to slow isoforms of myosin heavy chain ( wt, 5.3% IIa and 71.7% IIb; des −/−, 8.4% IIa and 61.4% IIb) and a decreased insulin-stimulated glucose uptake ( wt, 0.188 μmol/g muscle/20 min; des −/−, 0.085 μmol/g muscle/20 min). This work points to novel areas of influence of this cytoskeletal protein and directs future work to elucidate its function.


2020 ◽  
Vol 375 (1801) ◽  
pp. 20190400 ◽  
Author(s):  
Naresh Loudya ◽  
Tolulope Okunola ◽  
Jia He ◽  
Paul Jarvis ◽  
Enrique López-Juez

Defects in chloroplast development are ‘retrograde-signalled’ to the nucleus, reducing synthesis of photosynthetic or related proteins. The Arabidopsis cue8 mutant manifests virescence, a slow-greening phenotype, and is defective at an early stage in plastid development. Greening cotyledons or early leaf cells of cue8 exhibit immature chloroplasts which fail to fill the available cellular space. Such chloroplasts show reduced expression of genes of photosynthetic function, dependent on the plastid-encoded polymerase (PEP), while the expression of genes of housekeeping function driven by the nucleus-encoded polymerase (NEP) is elevated, a phenotype shared with mutants in plastid genetic functions. We attribute this phenotype to reduced expression of specific PEP-controlling sigma factors, elevated expression of RPOT (NEP) genes and maintained replication of plastid genomes (resulting in densely coalesced nucleoids in the mutant), i.e. it is due to an anterograde nucleus-to-chloroplast correction, analogous to retention of a juvenile plastid state. Mutants in plastid protein import components, particularly those involved in housekeeping protein import, also show this ‘retro-anterograde’ correction. Loss of CUE8 also causes changes in mRNA editing. The overall response has strong fitness value: loss of GUN1, an integrator of retrograde signalling, abolishes elements of it (albeit not others, including editing changes), causing bleaching and eventual seedling lethality upon cue8 gun1 . This highlights the adaptive significance of virescence and retrograde signalling. This article is part of the theme issue ‘Retrograde signalling from endosymbiotic organelles’.


2005 ◽  
Vol 16 (1) ◽  
pp. 11-18 ◽  
Author(s):  
Toru Seo ◽  
William S Blaner ◽  
Richard J Deckelbaum

1993 ◽  
Vol 71 (6) ◽  
pp. 765-778 ◽  
Author(s):  
S. D. Blakeley ◽  
D. T. Dennis

In plants, sucrose is the end product of photosynthesis and is converted to a wide variety of storage compounds in tissues such as seeds and tubers. The allocation of carbon from sucrose to the various metabolic pathways leading to these products will determine the quantity of each synthesized in the respective storage organs. If the level of the enzymes involved in the allocation of carbon could be changed by genetic manipulation, it is probable that the relative yields of the various storage products can also be altered. The initial breakdown of sucrose occurs in the cytosol of the cell. Many biosynthetic pathways, however, including those involved in the synthesis of storage products such as fatty acids, starch, and amino acids, occur in the plastid. The distribution of carbon substrates for these processes will be determined, to a large extent, by the flux of carbon through the glycolytic pathways found in both the cytosolic and plastid compartments. This article will discuss the importance and consequences of compartmentation, review the extent of our understanding of glycolysis and other enzymes and pathways regulating carbon allocation, and will speculate on the potential for the genetic manipulation of these pathways. Key words: genetic manipulation, carbon allocation, metabolism, glycolysis.


2002 ◽  
Vol 76 (23) ◽  
pp. 11960-11970 ◽  
Author(s):  
Jarmila Kralova ◽  
Andrew S. Liss ◽  
William Bargmann ◽  
Cullen Pendleton ◽  
Janani Varadarajan ◽  
...  

ABSTRACT The v-rel oncogene encoded by reticuloendotheliosis virus is the acutely transforming member of the Rel/NF-κB family of transcription factors. v-Rel is a truncated and mutated form of c-Rel and transforms cells by inducing the aberrant expression of genes regulated by Rel/NF-κB proteins. The expression of ch-IAP1, a member of the inhibitor-of-apoptosis family, is highly elevated in cells expressing v-Rel and contributes to the immortalization of cells transformed by this oncoprotein. In this study we demonstrate that the elevated expression of ch-IAP1 in v-Rel-expressing cells is due to an increased rate of transcription. The ch-IAP1 promoter was isolated, and four Rel/NF-κB binding sites were identified upstream of the transcription start site. Two κB sites proximal to the transcription start site were required for v-Rel to activate the ch-IAP1 promoter. While c-Rel also utilized these sites, a third more-distal κB site was required for its full activation of the ch-IAP1 promoter. Differences in the transactivation domains of v-Rel and c-Rel are responsible for their different abilities to utilize these sites and account for their differential activation of the ch-IAP1 promoter. Although c-Rel was a more potent activator of the ch-IAP1 promoter than v-Rel in transient reporter assays, cells stably overexpressing c-Rel failed to maintain high levels of ch-IAP1 expression. The reduction of ch-IAP1 expression in these cells correlated with the efficient regulation of c-Rel by IκBα. The ability of v-Rel to escape IκBα regulation allows for the gradual and sustained elevation of ch-IAP1 expression directly contributing to the transforming properties of v-Rel.


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