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SraD RNA
The MicA RNA (also known as SraD) is a small non-coding RNA that was discovered in ''E. coli'' during a large scale screen. Expression of SraD is highly abundant in stationary phase, but low levels could be detected in exponentially growing cells as well. Function This RNA binds the Hfq protein and regulates levels of gene expression by an antisense mechanism. It is known to target the OmpA gene in ''E. coli'' and occludes the ribosome binding site. Under conditions of envelope stress, micA transcription is induced. MicA, RybB RNA and MicL RNA transcription is under the control of the sigma factor sigma(E). In ''E.coli'', SraD also interacts in ''cis'' and ''trans'' with the mRNA species, ''luxS'', ''ompA a''nd ''phoP'', respectively. This observation describes MicA to be the first known sRNA to carry out antisense regulation in both structural configurations. MicA is known to interact with the mRNA encoding the quorum sensing synthase homolog, LuxS in E.coli and both RNAs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Structure
Protein secondary structure is the three dimensional conformational isomerism, form of ''local segments'' of proteins. The two most common Protein structure#Secondary structure, secondary structural elements are alpha helix, alpha helices and beta sheets, though beta turns and omega loops occur as well. Secondary structure elements typically spontaneously form as an intermediate before the protein protein folding, folds into its three dimensional protein tertiary structure, tertiary structure. Secondary structure is formally defined by the pattern of hydrogen bonds between the Amine, amino hydrogen and carboxyl oxygen atoms in the peptide backbone chain, backbone. Secondary structure may alternatively be defined based on the regular pattern of backbone Dihedral angle#Dihedral angles of proteins, dihedral angles in a particular region of the Ramachandran plot regardless of whether it has the correct hydrogen bonds. The concept of secondary structure was first introduced by Kaj Ulrik ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |