Unknown,Transcriptomics,Genomics,Proteomics

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Region-specific gene expression profiles in left atria of patients with valvular atrial fibrillation

ABSTRACT: Of 54,675 expressed sequence tags, microarray analysis revealed that 391 genes were differently expressed (>1.5-fold difference) between LA-PV junction and LAA, including genes related to arrhythmia, cell death, fibrosis, hypertrophy, and inflammation. Microarray and q-PCR produced parallel results in analyzing the expression of particular genes. The expression of paired like homeodomain-2 (PITX2) and its target protein (short stature homeobox-2 [SHOX2]) was greater in LA-PV junction than in LAA, which may contribute to arrhythmogenesis. Five genes related to thrombogenesis were up-regulated in LAA, which may implicate for the preferential thrombus formation in LAA. Genes related to fibrosis were highly expressed in LAA, which was reflected by intense ultrastructural changes in this region Paired LA-PV junction and left atrial appendage (LAA) specimens were obtained from 16 patients with persistent AF receiving valvular surgery. The Paired specimens were sent for microarray comparison. Selected results were validated by quantitative real time-PCR (q-PCR) and Western blotting. Ultrastructural changes in the atria were evaluated by immunohistochemistry.

ORGANISM(S): Homo sapiens

SUBMITTER: Yun-Shien Lee

PROVIDER: E-GEOD-41177 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Region-specific gene expression profiles in left atria of patients with valvular atrial fibrillation

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