Trypanosomes are protozoan parasites that have a major impact on human health and that of livestock. These parasites represent a very early branch in the eukaryotic lineage, and possess unique RNA processing mechanisms. The trypanosome signal recognition particle (SRP) is also unusual in being the first signal recognition particle described in nature to be comprised of two RNA molecules, the 7S...

The signal recognition particle (SRP) is a ribonucleoprotein complex with a key role in targeting and insertion of membrane proteins. The two SRP GTPases, SRP54 (Ffh in bacteria) and FtsY (SRα in eukaryotes), form the core of the targeting complex (TC) regulating the SRP cycle. The architecture of the TC and its stimulation by RNA has been described for the bacterial SRP system while this infor...

A new technique for multi-method dispatch, called Single-Receiver Projections and abbreviated SRP, is presented. It operates by performing projections onto single-receiver dispatch tables, and thus benefits from existing research into single-receiver dispatch techniques. It provides method dispatch in O(k), where k is the arity of the method. Unlike existing multi-method dispatch techniques, it...

OBJECTIVE To characterize the clinical course of myopathy associated with antibodies to signal recognition particle (SRP), or anti-SRP myopathy. DESIGN Case series. SETTING Keio University Hospitals and National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan. PATIENTS We reviewed clinical features of 27 patients with anti-SRP myopathy and analyzed dis...

Volumetric imaging allows global understanding of three-dimensional (3D) complex systems. Light-sheet fluorescence microscopy and optical projection tomography have been reported to image 3D volumes with high resolutions and at high speeds. Such methods, however, usually rely on fluorescent labels for chemical targeting, which could perturb the biological functionality in living systems. We dem...

The universally conserved signal recognition particle (SRP) is essential for the biogenesis of most integral membrane proteins. SRP scans the nascent chains of translating ribosomes, preferentially engaging those with hydrophobic targeting signals, and delivers these ribosome-nascent chain complexes to the membrane. Here, we present structures of native mammalian SRP-ribosome complexes in the s...

BACKGROUND Previous studies have demonstrated that synchronized coronary venous retroperfusion (SRP) can restore blood flow to the ischemic myocardium, resulting in infarct size reduction and improvement of the left ventricular function. Despite the nutritive blood flow achieved by SRP being relatively limited, SRP has been shown to improve washout of by-products from the ischemic myocardium. T...

The kinetics of the signal recognition particle(SRP)-mediated process of protein translocation across the endoplasmic reticulum membrane was studied by mathematical modeling and complementary experiments. The following results were obtained. (1) A model according to which SRP directs the ribosome, rather than the mRNA, to the membrane is supported by experiments designed to discriminate between...

We have previously reported that the DsbA signal sequence promotes efficient, cotranslational translocation of the cytoplasmic protein thioredoxin-1 via the bacterial signal recognition particle (SRP) pathway. However, two commonly used signal sequences, those of PhoA and MalE, which promote export by a posttranslational mechanism, do not export thioredoxin. We proposed that this difference in ...

OBJECTIVE Periodontitis is an inflammatory condition of the supporting dental tissues that is normally treated by mechanical removal of the subgingival biofilm. This mechanical treatment, generally known as scaling and root planing (SRP), is not entirely effective, and various adjunctive therapies have been investigated to improve the clinical outcome. This study evaluated the clinical effects ...