A Conserved Stem Loop Motif in the 5′Untranslated Region Regulates Transforming Growth Factor-β1 Translation

Transforming growth factor-β1 (TGF-β1) regulates cellular proliferation, differentiation, migration, and survival. The human TGF-β1 transcript is inherently poorly translated, and translational activation has been documented in relation to several stimuli. In this paper, we have sought to identify in cis regulatory elements within the TGF-β1 5′Untranslated Region (5′UTR). In silico analysis predicted formation of stable secondary structure in a G/C-rich element between nucleotides +77 to +106, and demonstrated that this element is highly conserved across species. Circular dichroism spectroscopy confirmed the presence of secondary structure in this region. The proximal 5′UTR was inhibitory to translation in reporter gene experiments, and mutation of the secondary structure motif increased translational efficiency. Translational regulation of TGF-β1 mRNA is linked to altered binding of YB-1 protein to its 5′UTR. Immunoprecipitation-RT-qPCR demonstrated a high basal association of YB-1 with TGF-β1 mRNA. However, mutation of the secondary structure motif did not prevent interaction of YB-1 with the 5′UTR, suggesting that YB-1 binds to this region due to its G/C-rich composition, rather than a specific, sequence-dependent, binding site. These data identify a highly conserved element within the TGF-β1 5′UTR that forms stable secondary structure, and is responsible for the inherent low translation efficiency of this cytokine

Kinship, ethnicity and religion in post-Communist societies:Russia's autonomous republic of Kabardino-Balkariya

International audienceAmong the consequences of and the subsequent breakup of the Soviet Union in 1991 has been the rise of ethnic nationalism. In the non-Russian parts of the former USSR this process has been accompanied by the reactivation of clan and other primordial social networks which under Soviet Communism had been in abeyance. This article, based on extensive field research material, examines political and social transformation in post-Communist Kabardino-Balkariya, a Russian Muslim autonomy in the North Caucasus. In particular, it analyses the nature of the nation-building policies of the ruling regime, and its relationship with the clan system. It is also concerned with Islamic revival and Islamic radicalism in the region and their correlation with the Islam-related republican and wider federal policies. The article reveals some grey areas in the current academic debate on ethnicity and nationalism and injects more conceptual syncretism into the study of post-Communist societies