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Suboptimal health status (SHS) is a reversible stage between health and illness that is characterized by health complaints, low energy, general weakness, and chronic fatigue. The Suboptimal Health Status Questionnaire-25 (SHSQ-25) has been validated in three major populations (African, Asian, and Caucasian) and is internationally recognized as a reliable and robust tool for health estimation in general populations. This study focused on the development of K-SHSQ-25, a Korean version of the SHSQ-25, from its English version.The SHSQ-25 was translated from English to Korean according to international guidelines set forth by the World Health Organization (WHO) for health instrument translation between different languages. A subsequent cross-sectional survey involved 460 healthy South Korean participants (aged 18-83 years; 65.4% females) to answer the 25 questions focusing on the health perspectives of 5 domains, 1) fatigue, 2) cardiovascular health, 3) digestive tract, 4) immune system and 5) mental health. The K-SHSQ-25 was further validated using tests for reliability, internal consistency, exploratory factor analysis (EFA), and confirmatory factor analysis (CFA).The version of K-SHSQ-25 achieved linguistic, cultural, and conceptual equivalence to the English version. The intraclass correlation coefficient (ICC) of test-retest reliability for individual items ranged from 0.88 to 0.99. Reliability estimates based on internal consistency reached a Cronbach's α of 0.953; the Cronbach's α for each domain ranged from 0.76 to 0.94. Regarding construct validity, the EFA of the K-SHSQ-25 generally replicated the multidimensional structure (fatigue, cardiovascular, digestive, immune system, and mental health) and 25 questions. The CFA revealed that the root mean square error of approximation (RMSEA), goodness-of-fit index (GFI) and adjusted goodness of fit index (AGFI) were excellent (RMSEA = 0.0690.08, GFI = 0.9290.90, AGFI = 0.9070.90). The five domains of the K-SHSQ-25 showed significant correlations with each other (r = 0.59-0.81, P0.001). The cut-off point of K-SHSQ-25 for SHS was determined as an SHS score of 25. The prevalence of SHS in this study was 60.0% (276/460), with 47.8% (76/159) for males and 58.5% for females (176/301).Our results indicate that the Korean version of SHSQ-25, K-SHSQ-25, is a transcultural equivalent, robust, valid, and reliable assessment tool for evaluating SHS in the Korean-speaking population.

Sulfur is essential for the health of plants and is an indispensable dietary component for human health and disease prevention. Its incorporation into our food supply is heavily reliant upon the uptake of sulfur into plant tissue and our subsequent intake. Dietary requirements for sulfur are largely calculated based upon requirements for the sulfur-containing amino acids (SAA), cysteine and methionine, to meet the demands for synthesis of proteins, enzymes, co-enzymes, vitamins, and hormones. SAA are found in abundance in animal sources and are relatively low in plants. However, some plants, particularly cruciferous and allium vegetables, produce many protective sulfur-containing secondary metabolites, such as glucosinolates and cysteine sulfoxides. The variety and quantity of these sulfur-containing metabolites are extensive and their effects on human health are wide-reaching. Many benefits appear to be related to sulfur's role in redox biochemistry, protecting against uncontrolled oxidative stress and inflammation; features consistent within cardiometabolic dysfunction and many chronic metabolic diseases of aging. This narrative explores the origins and importance of sulfur, its incorporation into our food supply and dietary sources. It also explores the overarching potential of sulfur for human health, particularly around the amelioration of oxidative stress and chronic inflammation, and subsequent chronic disease prevention.

Genetic factors influence susceptibility to diabetic kidney disease. Here we mapped genes mediating renal hypertrophic changes in response to diabetes. A survey of 15 mouse strains identified variation in diabetic kidney hypertrophy. Strains with greater (FVB/N(FVB)) and lesser (C57BL/6 (B6)) responses were crossed and diabetic F2 progeny were characterized. Kidney weights of diabetic F2 mice were broadly distributed. Quantitative trait locus analyses revealed diabetic mice with kidney weights in the upper quartile shared alleles on chromosomes (chr) 6 and 12; these loci were designated as Diabetic kidney hypertrophy (Dkh)-1 and -2. To confirm these loci, reciprocal congenic mice were generated with defined FVB chromosome segments on the B6 strain background (B6.Dkh1/2f) or vice versa (FVB.Dkh1/2b). Diabetic mice of the B6.Dkh1/2f congenic strain developed diabetic kidney hypertrophy, while the reciprocal FVB.Dkh1/2b congenic strain was protected. The chr6 locus contained the candidate gene; Ark1b3, coding aldose reductase; the FVB allele has a missense mutation in this gene. Microarray analysis identified differentially expressed genes between diabetic B6 and FVB mice. Thus, since the two loci identified by quantitative trait locus mapping are syntenic with regions identified for human diabetic kidney disease, the congenic strains we describe provide a valuable new resource to study diabetic kidney disease and test agents that may prevent it.

WHO defines health as "a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity." We coined and defined suboptimal health status (SHS) as a subclinical, reversible stage of the pre-chronic disease. SHS is a physical state between health and disease, characterized by health complaints, general weakness, chronic fatigue, and low energy levels. We have developed an instrument to measure SHS, Suboptimal Health Status Questionnaire-25 (SHSQ-25), a self-reported survey assessing five health components that has been validated in various ethnical populations. Our studies suggest that SHS is associated with the major components of cardiovascular health and the early onset of metabolic diseases. Besides subjective measure of health (SHS), glycans are conceived as objective biomarkers of SHS. Glycans are complex and branching carbohydrate moieties attached to proteins, participating in inflammatory regulation and chronic disease pathogenesis. We have been investigating the role of glycans and SHS in multiple cardiometabolic diseases in different ethnical populations (African, Chinese, and Caucasian). Here we present case studies to prove that a combination of subjective health measure (SHS) with objective health measure (glycans) represents a window of opportunity to halt or reverse the progression of chronic diseases.

Type 2 diabetes mellitus (T2DM) has been strongly associated with single nucleotide polymorphisms (SNPs) in the TCF7L2 gene. This study investigated the association between rs12255372, rs7903146 in the TCF7L2 gene and T2DM in a Ghanaian population. A case-control study design was used for this study. A total of 106 T2DM patients and 110 control participants were selected. Basic data collected included body mass index, blood pressure and socio-demographics. Fasting blood samples were collected and processed for: serum lipid analysis, plasma glucose estimation and plasma HbA1c estimation. Parts of the whole blood samples were used for DNA extraction using a modified salting-out method. Common and allele-specific primers were designed for genotyping using the Modified Tetra-Primer Amplification assay. Associations were evaluated using logistic regression models. The rs7903146 risk variant was significantly associated with 2.16 vs. 4.06 increased odds for T2DM in patients

Background Type-2 diabetes mellitus (T2DM) have been strongly associated with single nucleotide polymorphisms (SNPs) in the TCF7L2 gene. This study investigated the interplay between rs12255372 and rs7903146 with T2DM in a Ghanaian population. Methods A case-control design was used for this study. A total of 106 T2DM patients and 110 apparently healthy control participants were selected. Basic data collected included body mass index, blood pressure and socio-demographics. Fasting blood samples were collected and used for serum lipid analysis, HbA1c, glucose estimation and DNA extraction. Common and allele-specific primers were designed for genotyping using the Modified Tetra-Primer Amplification assay. Associations were evaluated using logistic regression models. Results The rs7903146 risk variant was significantly associated with 2.16 vs 4.06 increased odds for T2DM in patients 2 = 0.0001). Conclusion The association between rs7903146 and rs12255372 with T2DM looks to be more highly associated in a subgroup- women and those without T2DM family history, yet have cardiometabolic risk.

WHO defines health as “a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity.” We coined and defined suboptimal health status (SHS) as a subclinical, reversible stage of the pre-chronic disease. SHS is a physical state between health and disease, characterized by health complaints, general weakness, chronic fatigue, and low energy levels. We have developed an instrument to measure SHS, Suboptimal Health Status Questionnaire-25 (SHSQ-25), a self-reported survey assessing five health components that has been validated in various ethnical populations. Our studies suggest that SHS is associated with the major components of cardiovascular health and the early onset of metabolic diseases. Besides subjective measure of health (SHS), glycans are conceived as objective biomarkers of SHS. Glycans are complex and branching carbohydrate moieties attached to proteins, participating in inflammatory regulation and chronic disease pathogenesis. We have been investigating the role of glycans and SHS in multiple cardiometabolic diseases in different ethnical populations (African, Chinese, and Caucasian). Here we present case studies to prove that a combination of subjective health measure (SHS) with objective health measure (glycans) represents a window of opportunity to halt or reverse the progression of chronic diseases.

Genetic variants that are associated with susceptibility to type 2 diabetes (T2D) are important for identification of individuals at risk and can provide insights into the molecular basis of disease. Analysis of T2D in domestic animals provides both the opportunity to improve veterinary management and breeding programs as well as to identify novel T2D risk genes. Australian-bred Burmese (ABB) cats have a 4-fold increased incidence of type 2 diabetes (T2D) compared to Burmese cats bred in the United States. This is likely attributable to a genetic founder effect. We investigated this by performing a genome-wide association scan on ABB cats. Four SNPs were associated with the ABB T2D phenotype with p values &lt, 0.005. All exons and splice junctions of candidate genes near significant single-nucleotide polymorphisms (SNPs) were sequenced, including the genes DGKG, IFG2BP2, SLC8A1, E2F6, ETV5, TRA2B and LIPH. Six candidate polymorphisms were followed up in a larger cohort of ABB cats with or without T2D and also in Burmese cats bred in America, which exhibit low T2D incidence. The original SNPs were confirmed in this cohort as associated with the T2D phenotype, although no novel coding SNPs in any of the seven candidate genes showed association with T2D. The identification of genetic markers associated with T2D susceptibility in ABB cats will enable preventative health strategies and guide breeding programs to reduce the prevalence of T2D in these cats.

Clinical variation in patient responses to myocardial infarction (MI) has been difficult to model in laboratory animals. To assess the genetic basis of variation in outcomes after heart attack, we characterized responses to acute MI in the Collaborative Cross (CC), a multi-parental panel of genetically diverse mouse strains. Striking differences in post-MI functional, morphological, and myocardial scar features were detected across 32 CC founder and recombinant inbred strains. Transcriptomic analyses revealed a plausible link between increased intrinsic cardiac oxidative phosphorylation levels and MI-induced heart failure. The emergence of significant quantitative trait loci for several post-MI traits indicates that utilizing CC strains is a valid approach for gene network discovery in cardiovascular disease, enabling more accurate clinical risk assessment and prediction., Cardiology: Genetically diverse mice show human-like responses to heart attack Mice from a genetically diverse panel of inbred strains show a variety of biological outcomes after a heart attack (myocardial infarction), just as humans do. This ‘Collaborative Cross’ mouse resource—which is already widely used in other disciplines of biomedical research—thus provides a tractable system for investigating the genetic factors contributing to acute and chronic presentations of heart disease. Ekaterina Salimova from Monash University in Clayton, Australia, and colleagues experimentally induced myocardial infarctions in the 32 founder or recombinant strains from the Collaborative Cross. They documented large differences in survival, cardiac dilation and scar size among different strains. Gene expression profiling and quantitative trait locus mapping revealed a large number of candidate genes and molecular pathways linked to adverse outcomes. These could offer promising drug targets for treating the damage wrought by heart attacks.

Genetic variation conferring resistance and susceptibility to carcinogen-induced tumorigenesis is frequently studied in mice. We have now turned this idea to melanoma using the collaborative cross (CC), a resource of mouse strains designed to discover genes for complex diseases. We studied melanoma-prone transgenic progeny across seventy CC genetic backgrounds. We mapped a strong quantitative trait locus for rapid onset spontaneous melanoma onset to Prkdc, a gene involved in detection and repair of DNA damage. In contrast, rapid onset UVR-induced melanoma was linked to the ribosomal subunit gene Rrp15. Ribosome biogenesis was upregulated in skin shortly after UVR exposure. Mechanistically, variation in the ‘usual suspects’ by which UVR may exacerbate melanoma, defective DNA repair, melanocyte proliferation, or inflammatory cell infiltration, did not explain melanoma susceptibility or resistance across the CC. Instead, events occurring soon after exposure, such as dysregulation of ribosome function, which alters many aspects of cellular metabolism, may be important., eLife digest Melanoma is a type of skin cancer. Melanoma tumors form in the skin’s pigment-producing cells or melanocytes. Growing evidence points to complex interactions between genetics and environmental exposures that contribute to the risk of developing melanoma. Ultraviolet (UV) radiation from the sun causes genetic mutations in melanocytes. This sun exposure interacts with genetic variations that may make people more or less vulnerable to such DNA damage. For example, genetic variations that control skin color or the cell’s ability to repair DNA, and that influence how easily people develop sunburn, all affect whether UV damage leads to melanoma. However, some forms of melanoma are not caused by sun exposure at all. Most of the genetic variations linked to melanoma have a small effect on the risk of developing the disease. So, it is unlikely that these genes alone cause melanoma. Few studies have been able to map the complex interactions between genes and the environment that lead to melanoma. So far, it has been unclear if there are different genetic mechanisms that lead to an increased risk for sun-exposure linked melanoma and non-sun linked melanoma. Now, Ferguson et al. show that variations in the genes involved in DNA repair during normal cell growth are linked to non-sun linked melanoma. Sun-linked melanoma, on the other hand, was associated with genes involved in the production of proteins in part of the cell called ribosomes. In the experiments, the effects of both UV light and various genetic variations were assessed across many different strains of mice. Mutations that impair the cell’s ability to repair UV-induced DNA damage or that contribute to excessive inflammation in response to sunburn did not increase melanoma susceptibility in these experiments. Ferguson et al. show that the amount of UV-induced DNA damage alone does not explain melanoma risk, which may not always depend on skin pigmentation. The experiments also suggest that non-UV linked melanoma is caused by a different mechanism than sun exposure-linked melanoma. Learning more about different genetic factors that affect the risk of developing different types of melanoma may help scientists develop more specific treatments.

Variations in the proportion and number of specific immune cell types among healthy individuals are influenced by both heritable and nonheritable factors. Mouse models, subjected to fewer nonheritable factors than humans, allow the identification of genetic factors that shape the immune system. We characterized immunological trait variability in the Collaborative Cross (CC), a powerful genetic resource of recombinant inbred mouse strains derived from eight diverse founder strains. Of the 18 immunological traits studied in more than 60 CC strains, eight showed genome-wide significant linkage, revealing new genetic loci linked to specific immune traits. We also found that these traits were highly subject to heritable influences. As for humans, mouse immunological traits varied as a continuum rather than as discrete immunophenotypes. The CC thus represents a useful resource to identify factors that determine immunological variations, as well as defining other immune traits likely to be heritable in humans.

Different genes encode the α-actin isoforms that are predominantly expressed in heart and skeletal muscle. Mutations in the skeletal muscle α-actin gene (ACTA1) cause muscle diseases that are mostly lethal in the early postnatal period. We previously demonstrated that the disease phenotype of ACTA1 mouse models could be rescued by transgenic over-expression of cardiac α-actin (ACTC1). ACTC1 is the predominant striated α-actin isoform in the heart but is also expressed in developing skeletal muscle. To develop a translatable therapy, we investigated the genetic regulation of Actc1 expression. Using strains from The Collaborative Cross (CC) genetic resource, we found that Actc1 varies in expression by up to 24-fold in skeletal muscle. We defined significant expression quantitative trait loci (eQTL) associated with early adult Actc1 expression in soleus and heart. eQTL in both heart and soleus mapped to the Actc1 locus and replicate an eQTL mapped for Actc1 in BXD heart and quadriceps. We built on this previous work by analysing genes within the eQTL peak regions to prioritise likely candidates for modifying Actc1 expression. Additionally we interrogated the CC founder haplotype contributions to enable prioritisation of genetic variants for functional analyses. Methylation around the Actc1 transcriptional start site in early adult skeletal muscle negatively correlated with Actc1 expression in a strain-dependent manner, while other marks of regulatory potential (histone modification and chromatin accessibility) were unaltered. This study provides novel insights into the complex genetic regulation of Actc1 expression in early adult skeletal muscles.

The Collaborative Cross (CC) was designed to facilitate rapid gene mapping and consists of hundreds of recombinant inbred lines descended from eight diverse inbred founder strains. A decade in production, it can now be applied to mapping projects. Here, we provide a proof of principle for rapid identification of major-effect genes using the CC. To do so, we chose coat color traits since the location and identity of many relevant genes are known. We ascertained in 110 CC lines six different coat phenotypes: albino, agouti, black, cinnamon, and chocolate coat colors and the white-belly trait. We developed a pipeline employing modifications of existing mapping tools suitable for analyzing the complex genetic architecture of the CC. Together with analysis of the founders’ genome sequences, mapping was successfully achieved with sufficient resolution to identify the causative genes for five traits. Anticipating the application of the CC to complex traits, we also developed strategies to detect interacting genes, testing joint effects of three loci. Our results illustrate the power of the CC and provide confidence that this resource can be applied to complex traits for detection of both qualitative and quantitative trait loci.

Objective: To assess histopathological changes in clinically envenomed tiger snake patients and identify tissue specific localisation of venom toxins using immunohistochemistry. Samples: One feline and one canine patient admitted to the Murdoch Pet Emergency Centre (MPEC), Murdoch University with tiger snake (Notechis sp.) envenoming. Both patients died as a result of envenomation. Non-envenomed tissue was also collected and used for comparison. Methodology: Biopsy samples (heart, lung, kidney andskeletal muscle tissue) were retrieved 1-2 h post death and processed for histopathological examination using Haemotoxylin and Eosin, Martius Scarlet Blue and Periodic Acid Schiff staining. Tissues were examined by light microscopy and tissue sections subjected to immunohistochemical staining using in-house generated monoclonal and polyclonal antibodies against Notechis venoms. Results: Venom-induced pathological changes were observed in the lungs, kidneys and muscle tissue of both patients. Evidence, not previously noted, of procoagulant venom effects were apparent, with formed thrombi in the heart, lungs (small fibrillar aggregates and larger, discrete thrombi) and kidneys. Immunohistochemical assays revealed venom present in the pulmonary tissue, in and around the glomerular capsule and surrounding tubules in renal tissue and scattered throughout the Gastrocnemius muscle tissue. Conclusion: This work has shown pathological evidence of procoagulant venom activity supporting previous suggestions that an initial thrombotic state occurs in envenomed patients. We have shown that venom toxins are able to be localised to specific tissues, in this case, venom was detected in the lung, kidney and muscle tissues of clinically envenomed animals. Future work will examine specific toxin localisation using monoclonal antibodies and identify if antivenom molecules are able to reach their target tissues.

Type 2 diabetes (T2D) is associated with defective insulin secretion, which in turn contributes to worsening glycaemic control and disease progression. The genetic cause(s) associated with impaired insulin secretion in T2D are not well elucidated. Here we used the polygenic New Zealand Obese (NZO) mouse model, which displays all the cardinal features of T2D including hyperglycaemia to identify genes associated with β-cell dysfunction. A genome-wide scan identified a major quantitative trait locus (QTL) on chromosome 7 associated with defective glucose-mediated insulin secretion. Using congenic strains, the locus was narrowed to two candidate genes encoding the components of the KATP channel: Abcc8 (SUR1) and Kcnj11 (Kir6.2). The NZO Abcc8 allele was associated with a ∼211 bp deletion in its transcript and reduced expression of SUR1. Transgenic NZO mice were generated that expressed the WT Abcc8/Kcnj11 genes and displayed significant improvements in early-phase glucose-mediated insulin secretion and glucose tolerance, confirming Abcc8 as a causative gene. Importantly, we showed that despite improving β-cell function in the NZO transgenic mice, there was no enhancement of insulin sensitivity or body weight. This study provides evidence for a role of Abcc8 in early-phase glucose-mediated insulin secretion and validates this gene as a contributor to β-cell dysfunction in T2D.

The epidermal growth factor (EGF) receptor (EGF-R) is a protein tyrosine kinase receptor that is the target for high-affinity ligands, such as EGF and transforming growth factor alpha. EGF-R shares extensive homology with the erbB oncogene product of the avian erythroblastosis virus (12, 17, 46, 64), and overproduction and/or amplification of EGF-R has been detected in several different types of human cancers (12, 39, 40, 46, 47, 63), including breast cancer (20, 21, 30, 53). Extensive studies have shown that breast tumors which overexpress EGF-R are most often estrogen receptor (ER) negative and have a poor prognosis (57, 59). Despite the clinical importance of the EGF-R in human breast cancer, the molecular mechanisms governing the control of EGF-R gene expression in these cells remains to be fully elucidated. MDA-MB-468 and BT-20 estrogen-unresponsive breast cancer cell lines have similar phenotypes and overexpress EGF-R to similar degrees (1 × 106 to 2 × 106 binding sites per cell) (29, 32). Treatment of MDA-MB-468 cells with EGF increases EGF-R mRNA and protein levels (3, 32), due in part to a moderate transcriptional upregulation (19). However, the vast proportion of the EGF-induced increase in EGF-R mRNA levels in MDA-MB-468 cells cannot be accounted for by transcriptional enhancement. This suggests that posttranscriptional events must play a significant role in the regulation of EGF-R mRNA levels in these cells. Little is known of the regulation of EGF-R expression in BT-20 cells. The regulation of mRNA decay is a central mechanism in the control of gene expression (51). Specific cis-acting structural RNA motifs can confer instability to mRNAs under appropriate conditions. A major class of these regulatory cis elements comprises adenosine-uridine pentamers (AUUUA) which are termed AU-rich elements (AREs). Shaw and Kamen initially observed that an ARE in the 3′ untranslated region (3′-UTR) of granulocyte-macrophage colony-stimulating factor (GM-CSF) mRNA could stimulate the degradation of the normally stable β-globin mRNA, reducing the half-life from many hours to less than 30 min (56). Similarly, the 3′-UTR of c-fos, which contains a 69-nucleotide (nt) ARE, reduced the stability of β-globin mRNA (8, 9). AREs that function as RNA-destabilizing elements and target the mRNA for rapid degradation in the cytoplasm have been found in numerous mRNAs, including c-myc, junB, nur77, beta interferon, various interleukin (IL-1α, IL-2, and IL-3), and tumor necrosis factor (TNF) mRNAs (8, 9, 10, 13, 24, 31, 51, 56). In vivo, mice lacking AREs in their TNF gene have defective destabilization and translational regulation of TNF mRNA and also develop specific phenotypes, suggesting a potential etiopathological role for the ARE (31). Typically the ARE contains an AUUUA pentamer, repeated once or several times within the 3′-UTR. It is often found within a U-rich region of the mRNA. Recent work has suggested an ARE containing the nonamer UUAUUUA (U/A) (U/A) is more indicative of rapid destabilization (34, 68). Variations of the nonamer, such as extended pentamers (AUUUUA and AUUUUUA), are present in many complex AREs and have been identified as putative binding targets by a random RNA selection procedure (37). However, little is known of the role of isolated extended AU pentamers in the regulation of specific mRNAs in vivo. This is particularly relevant, as it is the combination of functionally and structurally distinct sequence motifs, such as AU pentamers, nonamers, extended AU pentamers, and U-rich stretches, that determines the ultimate destabilizing ability of each particular ARE. A family of proteins that bind to AU-rich, and sometimes U-rich, RNAs with high affinity has been characterized by RNA electrophoretic mobility shift assay (REMSA). In many cases, binding of these AU-rich region-binding proteins (AUBPs; 30 to 45 kDa) regulates the turnover of ARE-containing mRNAs (15, 27). One of the best-characterized AUBPs is HuR, a 36-kDa member of the elav family of RRM (RNA recognition motif)-containing RNA-binding proteins (27, 37). HuR binds with high affinity to ARE sequences (27, 37) and plays an active role in the stabilization of specific mRNAs containing AREs, such as GLUT1, c-fos, GM-CSF, plasminogen activator inhibitor type 2, and p21WAF1 mRNAs (18, 22, 26, 27, 38, 44). AUF1 is another well-characterized RNA-binding protein that binds to AREs, in particular that of c-myc (6, 16, 61, 67). AUF1 has been implicated in the regulation of many cytokine and G protein-coupled receptor mRNAs (61) and plays a major role in development (33). Interestingly, the binding of some AUBPs to AREs is regulated by activators of protein kinase C, such as phorbol esters (phorbol 12-myristate 13-acetate [PMA]) (4). The EGF-R mRNA contains four separate AU-rich sequences in the 3′-UTR. Interestingly, A431 epidermoid cancer cells express both the full-length EGF-R mRNA and a truncated EGF-R mRNA which lacks the 3′-UTR. The truncated EGF-R mRNA transcript is more stable than the full-length transcript (28), suggesting that one or more of the AU-rich sequences in the EGF-R mRNA 3′-UTR may contribute to basal and possibly regulated changes in EGF-R mRNA stability. We used breast cancer cells (MDA-MB-468 and BT-20) to determine the contribution of mRNA stability to the regulation of EGF-R expression. In both cell lines, EGF stabilized EGF-R mRNA >2-fold. Transfection experiments identified a novel 260-nucleotide (nt) AU-rich (66%) cis element in the 3′-UTR of EGF-R mRNA that contained two ∼75-nt AU-rich destabilizing sequences (EGF-R1A and EGF-R2A). trans-acting protein factors (55 to 80 kDa) that targeted the cis element and whose binding affinity was regulated by EGF and phorbol esters were identified. Mutational analysis demonstrated an important role for the extended AU pentamer at the 3′ end of the cis element in regulating EGF-R mRNA stability. These findings demonstrate a central role for mRNA turnover in the regulation of EGF-R expression in breast cancer cells and illustrate that complex cis element RNA-protein interactions contribute to basal and regulated EGF-R mRNA decay.

Cardiac actin ( ACTC ) is the fetal homologue of skeletal muscle actin ( ACTA1 ), and is switched off at birth in skeletal muscle but remains highly expressed in adult heart and in regenerating muscle. ACTC is 99% identical to ACTA1 protein, differing at only 4 amino acids. We previously showed an ACTC transgene could functionally replace ACTA1 in postnatal skeletal muscle of Acta1 knockout mice that normally die within a few days of birth, indicating that ACTC could have a therapeutic role in skeletal muscle actin diseases. We harnessed the power of two different recombinant inbred (RI) mouse models including BXD and the more recently developed Collaborative Cross (CC), to identify genetic elements controlling Actc expression. RI mice are genetic reference populations consisting of large numbers of inbred mouse strains descended from either 2 (BXD) or 8 (CC) founder strains. Characterization of these strains for a trait of interest allows for the mapping of gene(s) mediating that trait to genomic intervals called quantitative trait loci (QTL). We have identified in both RI sets a highly significant QTL regulating Actc expression in skeletal muscle. This QTL also regulates Actc expression in particular non-skeletal muscle tissues (eye and lung). Identification of the regulatory genetic element may provide a target for modifying expression of cardiac actin by therapeutic intervention.

Identification of genes underlying complex traits presents a challenge to which geneticists have responded with many diverse approaches. A common feature of these approaches is that different research groups must, on a case-by-case basis, replicate similar efforts in recruitment, genetic characterization, and analyses. To avoid this expensive "churning," an alternative approach has been proposed: production of an experimental genetic reference population, the Collaborative Cross, in which both genetic diversity and mapping power are maximized. Since this population consists of inbred mouse strains, further advantages are that it is essentially infinitely reproducible; genetic characterization needs to be performed only once; and the founder strains' genomes have been or will be sequenced, allowing imputation of allele sequences of all members of the reference population. Here we describe the establishment of such a genetic reference population, which we dub "The Gene Mine." Over 1000 genetically distinct lines have been established, descended from eight diverse founder strains. Preliminary phenotypic ascertainment of these strains indicates unexpected variability arising from independent assortment of genetic variants. The Gene Mine will be a powerful resource for characterization of essentially any mouse phenotype that has a genetic basis.

SUMMARYThe correlation between ontogenetic changes in the spectral absorption characteristics of retinal photoreceptors and expression of visual pigment opsins was investigated in the black bream, Acanthopagrus butcheri. To establish whether the spectral qualities of environmental light affected the complement of visual pigments during ontogeny, comparisons were made between fishes reared in: (1) broad spectrum aquarium conditions; (2) short wavelength-reduced conditions similar to the natural environment; or (3) the natural environment (wild-caught). Microspectrophotometry was used to determine the wavelengths of spectral sensitivity of the photoreceptors at four developmental stages: larval, post-settlement, juvenile and adult. The molecular sequences of the rod (Rh1) and six cone (SWS1, SWS2A and B, Rh2Aα and β, and LWS) opsins were obtained and their expression levels in larval and adult stages examined using quantitative RT-PCR. The changes in spectral sensitivity of the cones were related to the differing levels of opsin expression during ontogeny. During the larval stage the predominantly expressed opsin classes were SWS1, SWS2B and Rh2Aα, contrasting with SWS2A, Rh2Aβ and LWS in the adult. An increased proportion of long wavelength-sensitive double cones was found in fishes reared in the short wavelength-reduced conditions and in wild-caught animals, indicating that the expression of cone opsin genes is also regulated by environmental light.

Insulin hypersecretion may be an independent predictor of progression to type 2 diabetes. Identifying genes affecting insulin hypersecretion are important in understanding disease progression. We have previously shown that diabetes-susceptible DBA/2 mice congenitally display high insulin secretion. We studied this model to map and identify the gene(s) responsible for this trait.Intravenous glucose tolerance tests followed by a genome-wide scan were performed on 171 (C57BL/6 x DBA/2) x C57BL/6 backcross mice.A quantitative trait locus, designated hyperinsulin production-1 (Hip1), was mapped with a logarithm of odds score of 7.7 to a region on chromosome 13. Production of congenic mice confirmed that Hip1 influenced the insulin hypersecretion trait. By studying appropriate recombinant inbred mouse strains, the Hip1 locus was further localised to a 2 Mb interval, which contained only nine genes. Expression analysis showed that the only gene differentially expressed in islets isolated from the parental strains was Nnt, which encodes the mitochondrial proton pump, nicotinamide nucleotide transhydrogenase (NNT). We also found in five mouse strains a positive correlation (r2 = 0.90, p0.01) between NNT activity and first-phase insulin secretion, emphasising the importance of this enzyme in beta cell function. Furthermore, of these five strains, only those with high NNT activity are known to exhibit severe diabetes after becoming obese.Insulin hypersecretion is associated with increased Nnt expression. We suggest that NNT must play an important role in beta cell function and that its effect on the high insulin secretory capacity of the DBA/2 mouse may predispose beta cells of these mice to failure.

Purpose Diabetic retinopathy (DR) is a major cause of blindness globally. Investigating the underlying mechanisms of DR would be aided by a suitable mouse model that developed key features seen in the human disease, and did so without carrying genetic modifications. This study was undertaken to produce such a model. Methods Our panel of Collaborative Cross strains was screened for DR-like features after induction of diabetes by intravenous injection with alloxan or streptozotocin. Both flat-mounted whole-retina and histologic sections were studied for the presence of retinal lesions. Progression of DR was also studied by histologic examination of the retinal vascular and neural structure at various time points after diabetes onset. In addition, microarray investigations were conducted on retinas from control and diabetic mice. Results Features of DR such as degenerated pericytes, acellular capillaries, minor vascular proliferation, gliosis of Muller cells, and loss of ganglion cells were noted as early as day 7 in some mice. These lesions became more evident with time. After 21 days of diabetes, severe vascular proliferation, microaneurysms, preretinal damage, increased Muller cell gliosis, and damage to the outer retina were all obvious. Microarray studies found significant differential expression of multiple genes known to be involved in DR. Conclusions The FOT_FB strain provides a useful model to investigate the pathogenesis of DR and to develop treatments for this vision-threatening disease.

Sequence analysis of a 237 kb genomic fragment from the central region of the MHC has revealed that the HLA-B and HLA-C genes are contained within duplicated segments peri-B (53 kb) and peri-C (48 kb), respectively, and separated by an intervening sequence (IF) of 30 kb. The peri-B and peri-C segments share at least 90% sequence homology except when interrupted by insertions/deletions including Alu, L1, an endogenous retrovirus, and pseudogenes. The sequences of peri-B, IF, and peri-C were searched for the presence of Alu elements to use as markers of evolution, chromosomal rearrangements, and polymorphism. Of 29 Alu elements, 14 were identified in peri-B, 11 in peri-C, and 4 in IF. The Alu elements in peri-B and peri-C clustered phylogenetically into two clades which were classified as ``preduplication'' and ``postduplication'' clades. Four Alu J elements that are shared by peri-B and peri-C and are flanked by homologous sequences in their paralogous locations, respectively, clustered into a ``preduplication'' clade. By contrast, the majority of Alu elements, which are unique to either peri-B or peri-C, clustered into a postduplication clade together with the Alu consensus subfamily members ranging from platyrrhine-specific (Spqxcg) to catarrhine-specific Alu sequences (Y). The insertion of platyrrhine-specific Alu elements in postduplication locations of peri-B and peri-C implies that these two segments are the products of a duplication which occurred in primates prior to the divergence of the New World primate from the human lineage (35–44 mya). Examination of the paralogous Alu integration sites revealed that 9 of 14 postduplication Alu sequences have produced microsatellites of different length and sequence within the Alu 3′-poly A tail. The present analysis supports the hypothesis that HLA-B and HLA-C genes are products of an extended segmental duplication between 44 and 81 million years ago (mya), and that subsequent diversification of both genomic segments occurred because of the mobility and mutation of retroelements such as Alu repeats.