Ubiquitin protein E3 ligase ASB9 suppresses proliferation and promotes apoptosis in human spermatogonial stem cell line by inducing HIF1AN degradation

BACKGROUND: Spermatogonial stem cells (SSCs) are critical for sustaining spermatogenesis. Even though several regulators of SSC have been identified in rodents, the regulatory mechanism of SSC in humans has yet to be discovered. METHODS: To explore the regulatory mechanisms of human SSCs, we analyzed publicly available human testicular single-cell sequencing data and found that Ankyrin repeat and SOCS box protein 9 (ASB9) is highly expressed in SSCs. We examined the expression localization of ASB9 using immunohistochemistry and overexpressed ASB9 in human SSC lines to explore its role in SSC proliferation and apoptosis. Meanwhile, we used immunoprecipitation to find the target protein of ASB9 and verified its functions. In addition, we examined the changes in the distribution of ASB9 in non-obstructive azoospermia (NOA) patients using Western blot and immunofluorescence. RESULTS: The results of uniform manifold approximation and projection (UMAP) clustering and pseudotime analysis showed that ASB9 was highly expressed in SSCs, and its expression gradually increased during development. The immunohistochemical and dual-color immunofluorescence results displayed that ASB9 was mainly expressed in nonproliferating SSCs. Overexpression of ASB9 in the SSC line revealed significant inhibition of cell proliferation and increased apoptosis. We predicted the target proteins of ASB9 and verified that hypoxia-inducible factor 1-alpha inhibitor (HIF1AN), but not creatine kinase B-type (CKB), has a direct interaction with ASB9 in human SSC line using protein immunoprecipitation experiments. Subsequently, we re-expressed HIF1AN in ASB9 overexpressing cells and found that HIF1AN reversed the proliferative and apoptotic changes induced by ASB9 overexpression. In addition, we found that ABS9 was significantly downregulated in some NOA patients, implying a correlation between ASB9 dysregulation and impaired spermatogenesis. CONCLUSION: ASB9 is predominantly expressed in human SSCs, it affects the proliferation and apoptotic process of the SSC line through HIF1AN, and its abnormal expression may be associated with NOA.

Pathways of IFN-alpha Activation in Patients with Cervical Intraepithelial Neoplasia (CIN) / Vias de ativação de IFN-alfa em pacientes com Neoplasia Intraepitelial Cervical (NIC)

Abstract Objective The aim of the present study was to compare the local and systemic expression of the factors linked to the interferon alpha (IFN-α) activation pathway in different degrees of cervical intraepithelial neoplasia (CIN) and cervical cancer. Methods A total of 128 patients with CIN I, CIN II, CIN III and cervical cancer was evaluated. The real-time polymerase chain reaction (RT-PCR) technique was used to evaluate the gene expression of IFNR1, IFNR2, IFN-α, oligoadenylate synthase (2'5′OAS), cytokine signal suppressor 1 (SOCS) 1, SOCS3, signal transducer and transcription activator 1 (STAT1), and IRF9 from 128 biopsies. A total of 46 out of 128 samples were evaluated by flow cytometry for IFNAR1, IFNAR2, STAT1, IRF7 and IFN-α in peripheral blood cells. Results Patients with CIN II and III (63 samples) had a low local expression of IFNR1, but not IFNR2. Patients with some degree of injury showed high expression of SOCS1 and SOCS3. Systemically, patients with CIN II and III (20 samples) had a significant increase in IFNR1, IFNR2, STAT1, IRF7, and IFN-α in helper, cytotoxic T lymphocytes, and in monocytes. Conclusion Patients with high-grade lesions have increased systemic expression of IFN-α and its activation pathways in helper and cytotoxic T lymphocytes, as well as in monocytes due to an exacerbation of the immune response in these patients. This phenomenon is not accompanied by resolution of the lesion due to a defect in the IFN-α activation pathway that revealed by low local IFNAR1 expression and high local expression of SOCS1 and SOCS3.

Resumo Objetivo O objetivo do presente estudo foi comparar a expressão local e sistêmica dos fatores ligados à via de ativação do interferon alfa (IFN-α) em diferentes graus de neoplasia intraepitelial cervical (NIC) e câncer cervical (CA) Métodos Foram avaliados 128 pacientes com NIC I, NIC II, NIC III e CA. A técnica de reação de cadeia de polimerase em tempo real (RT-PCR, na sigla em inglês) foi realizada para avaliar a expressão gênica do receptor de interferon (IFNR) 1, IFNR2, IFN-α, 2′-5′- oligoadenilato sintetase (2′5′OAS), supressor de sinalização de citocina (SOCS)1, SOCS3, transdutor de sinal e ativador de transcrição 1 (STAT1) e fator regulador de interferon 9 (IRF9) das 128 biópsias. Das 128 amostras, 46 foram avaliadas por citometria de fluxo para IFNAR1, IFNAR2, STAT1, IRF7 e IFN-α em células de sangue periférico. Resultados Pacientes com NIC II e III (63 amostras) tiveram baixa expressão local de IFNR1 mas não de IFNR2. Pacientes com algum grau de lesão apresentaram alta expressão de SOCS1 e SOCS3. Sistemicamente, os pacientes com NIC II e III (20 amostras) tiveram um aumento significativo de IFNR1, IFNR2, STAT1, IRF7 e IFN-α em linfócitos T auxiliares, citotóxicos e monócitos. Conclusão Pacientes com lesões de alto grau apresentam expressão sistêmica aumentada de IFN-α e suas vias de ativação em linfócitos T auxiliares e citotóxicos, bem como em monócitos, devido à exacerbação da resposta imune nesses pacientes. Este fenômeno não é acompanhado pela resolução da lesão devido a um defeito na via de ativação do IFN-α que é revelado pela baixa expressão local de IFNR1 e alta expressão local de SOCS1 e SOCS3.

Tumor-associated macrophage is correlated with survival and SOCS protein expression in canine mammary carcinoma / Correlação do infiltrado macrofágico com a sobrevida e a expressão da proteína SOCS no carcinoma mamário canino

The inflammatory infiltrate in the tumor microenvironment, particularly in mammary tumors, has aroused great interest in oncology, to play different roles in the progression or tumor regression dependent on the types and cell subsets involved. The present study aimed to evaluate (1) the occurrence and intensity of macrophage infiltration in the mammary carcinoma microenvironment, (2) the expression of SOCS1 and SOCS3 proteins in tumor associated macrophages, (3) any association between these parameters and tumor development, as well as survival rates in female dogs. Twenty-two female dogs diagnosed as carcinoma arising in a mixed tumor (CMT) by histopathology were divided into two groups following mastectomy: dogs without metastasis (CMT(-)=11) and those with metastasis (CMT(+)=11). The following parameters were analyzed: tumor size, lymph node metastasis, clinical stage, histological grade, distribution and intensity of inflammatory infiltrate, tumor macrophage quantification by immunohistochemical analysis of SOCS1 and SOCS3 expression, and immunophenotyping of peripheral blood leukocytes by flow cytometry. Dogs with the higher proportions of macrophages in the inflammatory infiltrate (≥400/tumor) also had higher survival rates in comparison with dogs with less macrophages. Immunostaining revealed higher proportions of SOCS3-positive macrophages in dogs without lymph node metastasis, while SOCS1-positive macrophages were predominant in dogs with metastasis (p<0.05). Multivariate analysis found associations between survival rate and clinical staging (p=0.025), histological grade (p=0.007), and the expression of MHC-CI in circulating monocytes (p=0.018). Higher SOCS3 expression in activated macrophages within the inflammatory infiltrate were considered indicative of an antitumor immune response, improved clinicopathological parameters and longer survival, whereas SOCS1-related activation was associated with tumor progression, metastasis development and reduced survival in female dogs with mammary carcinomas.(AU)

O infiltrado inflamatório no microambiente tumoral, particularmente nos tumores mamários, tem despertado grande interesse na oncologia, por desempenhar diferentes funções na progressão ou regressão tumoral, dependendo dos tipos e subtipos celulares envolvidos. O presente estudo teve como objetivo avaliar: (1) a ocorrência e a intensidade do infiltrado macrofágico no microambiente do carcinoma mamário; (2) a expressão das proteínas SOCS1 e SOCS3 nos macrófagos associados ao tumor; (3) qualquer associação relacionada ao prognóstico entre estes parâmetros e o desenvolvimento tumoral, assim como a taxa de sobrevida. Vinte e duas cadelas diagnosticadas com carcinoma em tumor misto (CTM) por exame histopatológico foram divididas em dois grupos após a mastectomia: cadelas sem metástase (CTM(-)=11) e cadelas com metástase (CTM(+)=11). Foram analisados os seguintes parâmetros: tamanho do tumor, metástase para linfonodo, estadiamento clínico, grau histológico, distribuição e intensidade do infiltrado inflamatório, quantificação dos macrófagos tumorais por análise imuno-histoquímica da expressão de SOCS1 e SOCS3, e imunofenotipagem dos leucócitos (monócitos e linfócitos) do sangue periférico por citometria de fluxo. Cadelas que apresentavam maiores proporções de macrófagos no infiltrado inflamatório (≥400/tumor) também tiveram maior taxa de sobrevida em comparação àquelas com menos macrófagos. A imunomarcação revelou maiores proporções de macrófagos SOCS3-positivos em cães sem metástase para linfonodo, enquanto que macrófagos SOCS1-positivos foram predominantes naqueles com metástase (p<0,05). A análise multivariada identificou associações entre a taxa de sobrevida e o estadiamento clínico (p=0,025), grau histológico (p=0,007) e a expressão de MHC-CI em monócitos circulantes (p=0,018). A maior expressão de SOCS3 nos macrófagos ativados foi considerada indicativa de uma resposta imune antitumoral, melhores parâmetros clínicos e maior taxa de sobrevida, ao passo que a ativação relacionada com SOCS1 foi associada à progressão tumoral, desenvolvimento de metástase e redução na taxa de sobrevida em cadelas com carcinoma mamário.(AU)

Association of genetic polymorphisms of CISH with the risk of pulmonary tuberculosis in Zahedan, Southeast Iran

Abstract Background In the current study we aimed to find out the impact of cytokine-inducible Src homology 2 domain protein (CISH) gene polymorphisms on the risk of pulmonary tuberculosis (PTB) in a sample of Iranian population. Materials and methods Polymorphisms of CISH rs2239751, rs414171, and rs6768300 were determined in 200 PTB patients and 200 healthy subjects using T-ARMS-PCR or PCR-RFLP method. Results The results showed that rs414171 A>T genotypes significantly decreased the risk of PTB (OR = 0.16, 95% CI = 0.10–0.27, p < 0.0001, AT vs AA; OR = 0.31, 95% CI = 0.14–0.68, p < 0.0001, TT vs AA; OR = 0.19, 95% CI = 0.12–0.29, p < 0.0001, AT+TT vs AA; OR = 0.29, 95%CI = 0.20–0.42, p < 0.0001, T vs A). For rs6768300, the findings indicated that this variant decreased the risk of PTB (OR = 0.52, 95% CI = 0.33–0.82, p = 0.005, CG vs GG; OR = 0.57, 95% CI = 0.38–0.87, p = 0.012, C vs G). No significant association was observed between CISH rs2239751 polymorphism and risk/protection of PTB. Conclusion Our findings indicated that CISH rs414171 and rs6768300 variants might be associated with protection from PTB.

Fatores ambientais associados ao tempo de decisão para procura de atendimento no infarto do miocárdio / Environmental factors associated with the decision time for seeking care in myocardial infarction / Factores ambientales asociados con el tiempo de decisión para la búsqueda de atención en el infarto de miocardio

Objetivou-se estimar o tempo de decisão para procura de atendimento (TD) para homens e mulheres com infarto agudo do miocárdio (IAM); analisar a influência de variáveis ambientais no TD e a interação entre gênero e variáveis ambientais para o desfecho TD. Estudo transversal, envolvendo cem pacientes, entrevistados em hospitais de Salvador. Na análise dos dados empregou-se o Qui-quadrado ou Exato de Fisher e o Modelo de Regressão Linear Robusto. Predominou o IAM ocorrido no domicílio, familiares no entorno, e os pacientes sendo alvo de ações equivocadas. Observou-se TD elevado para mulheres (0,9h) e homens (1,4h). Aqueles em casa no início dos sintomas tiveram maior TD, comparados aos no trabalho e menor em relação aos em via pública (p=0,047). Houve interação estatisticamente significante entre gênero e viver acompanhado; e entre gênero e ter companheiro e filhos no entorno, para o desfecho TD. O cuidar em enfermagem focalizado nas especificidades de fatores ambientais e de gênero pode otimizar o atendimento precoce.

The purpose was to estimate the decision time (DT) for searching for attendance for men and women suffering from acute myocardial infarction (AMI); and to analyze the influence of surrounding variables in the DT. Transversal study, involving one hundred patients interviewed in hospitals of Salvador-BA, Brazil. For data analysis, it was used the chi-squared or Fisher’s exact test, and the Robust Linear Regression Model. AMI at the home predominated, with family members and patients receiving mistaken actions. A high DT was observed both, for women (0.9h) and men (1.4h). Those at home during the initial symptoms had higher DT, compared to those at work; and lower in relation to those in public spaces (p=0.047). Statistically significant interaction occurred among gender and the fact of living with company; and among gender and having a companion and children, for the outcome of the DT. Nursing care focused on the specificity of surrounding factors and gender can optimize early attendance.

Se objetivó estimar el tiempo de decisión para buscar atendimiento (TD) para hombres y mujeres con infarto agudo de miocardio (IAM); analizar la influencia de variables ambientales en TD y la interacción entre genero y variables ambientales para el desfecho del TD. Estudio transversal, envolviendo cien pacientes entrevistados en hospitales de Salvador-BA, Brasil. En el análisis se utilizó el chi-cuadrado o el Teste Exacto de Fisher y el Modelo de Regresión Linear Robusto. Predominó el IAM en el domicilio, familiares en el entorno y con pacientes siendo objeto de acciones equivocadas. Se observó TD elevados para mujeres (0,9h) y hombres (1,4h). Aquellos en sus casas en el inicio de los síntomas tuvieron mayor TD, comparados a los en el trabajo, y menor en relación aquellos en vía pública (p=0,047). Hubo interacción estadísticamente significante entre genero y vivir acompañado y entre genero y tener compañero e hijos en el entorno, para el desfecho del TD. El cuidar en enfermería focalizado en especificidades de factores ambientales y de géneros puede optimizar el atendimiento precoce.

Myxovirus resistance, osteopontin and suppressor of cytokine signaling 3 polymorphisms predict hepatitis C virus therapy response in an admixed patient population: comparison with IL28B

OBJECTIVES: Suppressor of cytokine signaling 3, myxovirus resistance protein and osteopontin gene polymorphisms may influence the therapeutic response in patients with chronic hepatitis C, and an association with IL28 might increase the power to predict sustained virologic response. Our aims were to evaluate the association between myxovirus resistance protein, osteopontin and suppressor of cytokine signaling 3 gene polymorphisms in combination with IL28B and to assess the therapy response in hepatitis C patients treated with pegylated-interferon plus ribavirin. METHOD: Myxovirus resistance protein, osteopontin, suppressor of cytokine signaling 3 and IL28B polymorphisms were analyzed by PCR-restriction fragment length polymorphism, direct sequencing and real-time PCR. Ancestry was determined using genetic markers. RESULTS: We analyzed 181 individuals, including 52 who were sustained virologic responders. The protective genotype frequencies among the sustained virologic response group were as follows: the G/G suppressor of cytokine signaling 3 (rs4969170) (62.2%); T/T osteopontin (rs2853744) (60%); T/T osteopontin (rs11730582) (64.3%); and the G/T myxovirus resistance protein (rs2071430) genotype (54%). The patients who had ≥3 of the protective genotypes from the myxovirus resistance protein, the suppressor of cytokine signaling 3 and osteopontin had a greater than 90% probability of achieving a sustained response (p<0.0001). The C/C IL28B genotype was present in 58.8% of the subjects in this group. The sustained virological response rates increased to 85.7% and 91.7% by analyzing C/C IL28B with the T/T osteopontin genotype at rs11730582 and the G/G suppressor of cytokine signaling 3 genotype, respectively. Genetic ancestry analysis revealed an admixed population. CONCLUSION: Hepatitis C genotype 1 patients who were responders to interferon-based therapy had a high frequency of multiple protective polymorphisms in the myxovirus ...

Estudo da participação de reguladores negativos endógenos da atividade de STAT1 e STAT3 (SOCS1 e SOCS3) na doença periodontal experimental / Role of endogenous negative regulators of STATI and STAT3 (SOCS1 and SOCS3 during experimental periodontal disease

A expressão de citocinas inflamatórias é um processo estritamente regulado por mecanismos variados, incluindo o controle da sinalização intracelular e da atividade transcricional por inibidores endógenos, os quais são pouco estudados e compreendidos. Três grupos de proteínas: SHP, PIAS e SOCS inibem de maneira distinta e específica a transdução de sinais pela via JAK/STAT, bem como a atividade dos fatores de transcrição, eventos que modulam a expressão de diversas citocinas. As doenças periodontais estão associadas à inflamação persistente, com elevados níveis de citocinas proinflamatórias, no entanto praticamente não existem informações sobre a participação destes mecanismos de regulação nas diferentes condições clínicas periodontais. Os objetivos deste projeto incluíram avaliar a cinética de expressão das proteínas SOCS1 e SOCS3 e suas proteínas-alvo, STAT1 e STAT3, respectivamente, durante a evolução da doença periodontal. Foram utilizados 36 ratos Wistar divididos em 2 grupos: DP - doença periodontal induzida por 2 métodos: ligaduras ao redor dos 1os molares inferiores e injeções de 60 µg de LPS de E. coli no tecido gengival palatino dos molares superiores, 3x/semana; Grupo controle negativo - recebeu apenas injeções de PBS (veículo). Os ratos foram sacrificados 7, 15 e 30 dias após a indução da doença periodontal para avaliação histológica e análise macroscópica da perda óssea alveolar. A expressão de SOCS1 e SOCS3 e a ativação de STAT1 e STAT3 foram avaliadas nas biópsias gengivais por PCR em tempo real e Western blot. Ambos os modelos apresentaram significante e progressiva perda óssea dos 7 aos 30 dias. A inflamação foi evidente já no período de 7 dias em ambos os modelos, porém enquanto manteve-se similar nos demais períodos no modelo de indução por LPS, apresentou uma diminuição na severidade da inflamação no modelo de ligadura aos 30 dias. Houve um significante (p<0.05) aumento na expressão gênica de SOCS1 e SOCS3 no grupo DP comparado com o grupo controle aos 15 dias (ambos os modelos) e aos 30 (modelo de indução por ligadura). A ativação de STAT1 e -3 foram aumentadas nos períodos iniciais no modelo por ligadura e nos períodos mais tardios no modelo de LPS. Estes resultados sugerem que SOCS1 e -3 participam na regulação do processo inflamatório responsável pela destruição periodontal

Inflammatory cytokine gene expression is a process strictly regulated by various mechanisms, including the negative regulation of signaling of cytokine receptors and of the activity of transcription factors such as STATs. These mechanisms involve endogenous proteins and are largely unknown, especially in periodontal diseases. Three groups of proteins, SHP, PIAS and SOCS modulate in a fairly specific manner JAK/STAT signaling and/or STAT activity. Periodontal diseases are infectious-inflammatory conditions of the supporting tissues of the teeth associated with increased levels of proinflammatory cytokines, but there are no information regarding the role of these endogenous mediators of JAK/STAT during its course. The aims of this study included the evaluation of the expression kinetics of inducible negative regulators and their target proteins during the course of experimentally induced periodontal disease. 36 Wistar rats were divided into two groups: PD - experimental periodontal disease induced by two methods: ligature placement around the first mandibular molars and E. coli lipopolysaccharide (LPS) injections into the palatal gingival tissues of the maxillary molars, 3x/week, and Negative Control group. Rats were sacrificed 07, 15 and 30 days after disease induction for histological evaluation of periodontal inflammation and macroscopic analysis of alveolar bone loss. SOCS expression and the activation status of STAT1 and STAT3 were evaluated in gingival biopsies by real time PCR and Western Blot. Both disease models presented significant progressive bone loss from 7 to 30 days. Inflammation was evident and similar for all the periods in LPS injected sites; however, a decrease on severity at the end of the experimental period was observed in the ligature model. There was a significant (p<0.05) increase on SOCS1 and SOCS3 gene expression in PD compared to control group at 15 (both disease models) and 30 days (ligatureinduced model). The activation of STAT1 and STAT3 were increased in earlier periods in the ligature model and in later periods in the LPS model. This study suggests that SOCS 1 and 3 participate in the regulatory mechanism of the inflammatory process responsible for the periodontal disease destruction

Aspectos imunológicos na cardiopatia chagásica crônica / Immunological features in Chagas cardiomyopathy

A patogenia da cardiomiopatia chagásica crônica ainda é pouco conhecida, e diversos mecanismos patogênicos foram propostos, como a disautonomia cardíaca, os distúrbios da circulação microvascular, e o dano tecidual imunológico-inflamatório. As observações de que a miocardite é mais frequente e intensa nos estágios mais avançados da doença e de que o prognóstico da cardiopatia chagásica crônica é pior que o de outras cardiomiopatias dilatadas de etiologia não-inflamatória sugerem que o infiltrado inflamatório desempenha papel importante no dano miocárdio. Na última década, tem sido evidenciada a participação de citocinas inflamatórias e de quimiocinas na gênese do infiltrado inflamatório e dano tecidual, assim como de polimorfismos genéticos de genes envolvidos na resposta inflamatória. Cardiopatas chagásicos apresentam produção periférica aumentada de interferon-gama e de fator de necrose tumoral alfa (TNF-alfa), comparativamente a pacientes da forma indeterminada, e linfócitos T Th1, produtores de interferon-gama e TNF-alfa, são frequentes no infiltrado inflamatório da cardiopatia chagásica crônica. Neste trabalho, revisaremos os mecanismos imunológicos e moleculares de dano miocárdico na cardiopatias chagásica crônica humana, com ênfase nos resultados obtidos pelo nosso grupo de pesquisa.

Cross-talk das vias de sinalização de insulina e angiotensina II: implicações com a associação entre diabetes mellitus e hipertensão arterial e doença cardiovascular / Insulin and angiotensin II signaling pathways cross-talk: implications with the association between diabetes mellitus, arterial hypertension and cardiovascular disease

Insulina (Ins) e Angiotensina II (AII) são fundamentais no controle de dois sistemas vitais e inter-relacionados: o metabólico e o cardiocirculatório, respectivamente. A disfunção de qualquer um desses hormônios pode levar ao desenvolvimento de duas doenças de alta prevalência, muitas vezes concomitantes e, talvez, com fisiopatologia integrada - diabetes mellitus (DM) e hipertensão arterial (HA). Vários estudos mostram que os sistemas de sinalização intracelular de Ins e AII estão conectados e influenciam um ao outro. Esta comunicação molecular ocorre em diferentes etapas da sinalização celular e é importante para vários fenômenos fisiológicos, desde o desenvolvimento de hipertrofia cardíaca e aquisição de energia pelo coração, até a ação de drogas anti-hipertensivas. No nível extracelular, a enzima de conversão de angiotensina regula a síntese de AII e o acúmulo de bradicinina, e ambos desempenham papel regulador sobre a sinalização de Ins. No nível intracelular, a interação dos sinais de Ins e AII ocorre em dois momentos distintos. Inicialmente, em etapas mais precoces da sinalização celular, a AII, atuando através da cascata JAK-2/IRS-1/PI3-quinase, JNK e ERK, provoca a fosforilação em serina e a conseqüente inibição de elementos-chave da via de sinalização da Ins. Finalmente, a AII induz a expressão da proteína regulatória SOCS-3, que impõe um controle mais tardio sobre o sinal de Ins. Esta revisão discute os avanços mais recentes neste campo e a importância dessa interação molecular na fisiopatologia e na associação clínica de DM e HA.

Insulin (Ins) and angiotensin II (AII) play pivotal roles in the control of two vital and closely related systems: the metabolic and the circulatory, respectively. A failure in the proper action of each of these hormones results, to a variable degree, in the development of two highly prevalent and commonly overlapping diseases - diabetes mellitus (DM) and hypertension (AH). In recent years, a series of studies has revealed a tight connection between the signal transduction pathways that mediate Ins and AII actions in target tissues. This molecular cross-talk occurs at multiple levels and plays an important role in phenomena that range from the action of anti-hypertensive drugs to cardiac hypertrophy and energy acquisition by the heart. At the extracellular level, the angiotensin-converting enzyme controls AII synthesis but also interferes with Ins signaling through the proper regulation of AII and the accumulation of bradykinin. At an early intracellular level, AII, acting through JAK-2/IRS-1/PI3-kinase, JNK and ERK, may induce the serine phosphorylation and inhibition of key elements of the Ins-signaling pathway. Finally, by inducing the expression of the regulatory protein SOCS-3, AII may impose a late control on the Ins signal. This review will focus on the main advances obtained in this field and will discuss the implications of this molecular cross-talk in the common clinical association between DM and AH.

Characterization of variation in the canine suppressor of cytokine signaling-2 (SOCS2) gene

Suppressor of cytokine signaling 2 (SOCS2) is a negative regulator of growth hormone signaling. The deletion of SOCS2 in mice results in a 30-50% increase in post-natal growth. In an effort to identify polymorphisms in the SOCS2 gene that may be associated with body size in dogs, we characterized the canine SOCS2 gene and analyzed its genetic diversity among small and large dog breeds. The study was carried out on a total of 520 dogs from 66 different breeds. Dogs were classified as large or small based on height and weight as determined by their respective American Kennel Club breed standards. The SH2 and SOCS domains of the canine SOCS2 gene were sequenced in 32 dogs from different breeds. Only one non-synonymous sequence variant (DQ415457:g.326G>T) was detected which corresponds to an amino acid change (Asp127Tyr). All samples were genotyped by PCR/RFLP and the allele frequencies were determined for each dog breed. The T allele was distributed primarily among European large dog breeds with a gene frequency ranging from 0.72 to 0.04. The nature of the nucleotide change and the effect on the protein together with the finding of a QTL related to body size in the same CFA15 region by other researchers suggest canine SOCS2 as a potential candidate gene for body size in dogs. Future studies will be needed to clarify the role of the 326G>T polymorphism and its interaction with genes like growth hormone and insulin-like growth factor 1