RNA Overwriting of Cellular mRNA by Cas13b-Directed RNA-Dependent RNA Polymerase of Influenza A Virus.

Dysregulation of mRNA processing results in diseases such as cancer. Although RNA editing technologies attract attention as gene therapy for repairing aberrant mRNA, substantial sequence defects arising from mis-splicing cannot be corrected by existing techniques using adenosine deaminase acting on RNA (ADAR) due to the limitation of adenosine-to-inosine point conversion. Here, we report an RNA editing technology called "RNA overwriting" that overwrites the sequence downstream of a designated site on the target RNA by utilizing the RNA-dependent RNA polymerase (RdRp) of the influenza A virus.

Adenosine triphosphate-linked concentration of calcium ions in a particulate fraction of rabbit muscle.

ATPase and ATP-dependent calcium ion concentration was studied with a membrane fraction isolated from homogenized rabbit skeletal muscle by differential centrifugation. Electron micrographs of the fraction indicate that it consists mainly of resealed tubules and vesicles of the endoplasmic reticulum. The up-to-1400-fold concentration of calcium in this fraction might be explained by proposing the existence of an energy-requiring system for the transport of calcium ions into the tubules or vesicles.

Is phosphorylation the main physiological action of myosin light chain kinase?

The 155-kDa component of bovine stomach, which exhibits a strong actomyosin (AM) activating activity and a relatively weak myosin light chain kinase (MLCK) activity, has a strong affinity for the actin filament and the actin-binding site is confined to an 80 amino acid residue on its N-terminal side. This affinity may play a crucial role in AM activation. Some reagents preferentially abolish either the AM-activating effect or MLCK activity.

Subgingival plaque formation on single and polycrystal aluminum ceramics.

A study was conducted to investigate subgingival plaque formation on two types of dental implant material in the human oral cavity. Fifteen teeth affected by severe periodontitis and scheduled for extraction in five patients were selected. After thorough root planing, inlay cavities were prepared from the gingival margin to 5 mm subgingivally.

Complexes of myosin subfragment 1 with pyrophosphate and with adenosine diphosphate as studied by phosphorus-31 nuclear magnetic resonance.

Myosin subfragment-1.pyrophosphate (S1.PPi) complex and S1.

Isolation of cDNA for bovine stomach 155 kDa protein exhibiting myosin light chain kinase activity.

Two proteins with myosin light chain kinase activity and electrophoretic molecular weights of 155,000 and 130,000 were each isolated from bovine stomach smooth muscle [Kuwayama, H., Suzuki, M., Koga, R.

[Inorganic ions versus proteins in biological functions].

Physiological studies on inorganic ions were historically reviewed. Extremely asymmetric distribution of Ca2+ inside and outside the cell is the basis of its unparalleled role in intracellular processes. This must be rightly appreciated from the viewpoint of the origin of life, where the attention has exclusively been focused on the protein so far.

Histone H1 kinase specific to the SPKK motif.

A protein kinase phosphorylating sea urchin spermatogenous histones, H1 and H2B, was found in sea urchin egg homogenate and purified. The kinase is activated by cAMP and is composed of two different types of subunits with molecular masses 41 and 46 kDa. The kinase phosphorylates a peptide, Ser-Pro-Arg-Lys-Ser-Pro-Arg-Lys, which is a double repeat of the DNA-binding SPKK motif [Suzuki M.

Sea urchin protease specific to the SPKK motif in histone.

A protease activity specific to spermatogenous histones was found in the egg extract of sea urchin. The enzyme responsible for this activity, named SPKK protease because of its substrate specificity, was purified as a monomeric 28 kDa protein. SPKK protease activity is inhibited by leupeptin and is specific to the repeat of sequences like Ser-Pro-Lys-Lys (the SPKK motif) [Suzuki, M.

Preparation of protein components exhibiting myosin light chain kinase activities from bovine aorta: discrepancies between its enzyme activity and actomyosin activating effect.

1) Two protein components, 155 and 130 kDa in their electrophoretic molecular weights, respectively, were isolated in a homogeneous state from bovine aorta; they showed both the superprecipitation-inducing effect on desensitized natural actomyosin and the myosin light chain kinase (MLCK) action on gizzard myosin. 2) The superprecipitating activity of the 155 kDa component was 5 time higher than that of the 130 kDa component on the basis of equivalent MLCK activity. 3) The same procedure was applied to bovine stomach, giving rise to a 155 kDa component in a homogeneous state as in the case of aorta, but the 130 kDa component thus prepared was contaminated by higher molecular weight components.

Isolation from bovine brain of 155 kDa component exhibiting myosin light chain kinase activity.

1) Taking myosin light chain kinase (MLCK) activity as the index, bovine extract was fractionated by the use of anion-exchange chromatography, cation-exchange chromatography, and calmodulin affinity chromatography. The kinase activity of the fraction thus obtained was elevated up to about 12,400 times over that of the original crude extract. 2) The fraction mentioned above was subjected again to anion exchange chromatography.

Preparation of tubulin from Caulerpa, a marine green alga, using casein as a protective agent against proteolytic degradation.

Bidirectional organelle movements taking place in the cytoplasm of the rhizomes of Caulerpa, a coenocytic marine green alga, have been indicated to be dependent on microtubules (Kuroda, K. & Manabe, E. (1983) Proc.

Ca2+ in contractile processes.

The concept of Ca2+ regulation, first discovered and developed in muscle research, is historically surveyed. Ca2+ regulation mechanisms in actomyosin-dependent contractile processes are compared, emphasis being placed on the great diversity. The mode of action of Ca2+ is discussed with the examples of troponin and calmodulin, the most differentiated and conservative Ca2+-receptor proteins, respectively.

Ca2+ in the heart.

Ca research in the heart was historically surveyed. First, reference was made to the development of the concept involving Ca2+ in the contraction of skeletal muscle. This was followed by an overview of studies on Ca regulation in cardiac muscle.