Tight junctions are one mode of cell-cell adhesion in epithelial and endothelial cellular sheets. They act as a primary barrier to the diffusion of solutes through the intercellular space, create a boundary between the apical and the basolateral plasma membrane domains, and recruit various cytoskeletal as well as signalling molecules at their cytoplasmic surface. New insights into the molecular architecture of tight junctions allow us to now discuss the structure and functions of this unique cell-cell adhesion apparatus in molecular terms.

Multifunctional strands in tight junctions.

Adenosine 3',5'-phosphate in biological materials. I. Purification and properties of cyclic 3',5'-nucleotide phosphodiesterase and use of this enzyme to characterize adenosine 3',5'-phosphate in human urine.

Lang, Florian, Gillian L. Busch, Markus Ritter, Harald Volkl, Siegfried Waldegger, Erich Gulbins, and Dieter Haussinger. Functional Significance of Cell Volume Regulatory Mechanisms. Physiol. Rev. ...

Functional Significance of Cell Volume Regulatory Mechanisms

One of the challenges of contemporary cell biology is to unravel how the molecular composition of the different cellular compartments is generated and maintained during the cell cycle. In animal cells most of the efforts have been directed toward the study of how newly synthesized proteins are transported to their correct cellular destinations, whereas the lipids, which make up the framework of the membranes in the cell, have been given much less attention. Lipid biochemistry has remained a fairly esoteric branch of molecular cell biology. This situation is now gradually changing with the discovery of phosphoinositide involvement in signal transduction (Ber- ridge,

/pdf/lipid-sorting-in-epithelial-cells-o0fb47hred.pdf

Lipid sorting in epithelial cells.

https://www.jbc.org/content/243/13/3763.full.pdf

An Adenosine 3',5'-Monophosphate-dependant Protein Kinase from Rabbit Skeletal Muscle

/pdf/the-similarity-of-effects-of-vasopressin-adenosine-3-5-qyeuu2g51j.pdf

The similarity of effects of vasopressin, adenosine-3′,5′-phosphate (cyclic amp) and theophylline on the toad bladder

https://www.amjmed.com/article/0002-9343(67)90093-9/pdf

The role of adenosine 3′,5′-phosphate in the action of antidiuretic hormone

Membrane-bound lectins and some lipid probes are incapable of passing through the tight junction region of epithelial cell membranes. The lectins are immobile on the cell surf ace, but lipid probes diffuse freely in the membrane. The ability of a lipid probe to pass the tight junction is correlated with its ability to ‘flip-flop’ to the inner monolayer of the cell membrane bilayer

Membrane asymmetry in epithelia: is the tight junction a barrier to diffusion in the plasma membrane?

THE prostaglandins (PGE), a group of naturally occurring fatty acids, have been isolated from a number of sources including sheep vesicular glands and human vesicular plasma1,2. The chemical nature and separation of this series of related analogues have been reported in detail2–4. They have profound effects on blood pressure and on smooth muscle contractility, and are also known to interfere with the action of a variety of hormones on adipose tissue5–7. Because of the possibility that the prostaglandins may have other physiological effects of a more general nature, and perhaps serve as regulators of hormone action in certain tissues, the effect of one of them, PGEI, on the response of the toad bladder to vasopressin, theophylline and adenosine 3′,5′-monophosphate (cyclic-AMP) was examined. All three of the latter compounds, when added to the serosal surface of the isolated bladder of Bufo marinus, increase the osmotic flow of water across this membrane. It has been suggested that vasopressin exerts its permeability effects here and in the kidney by increasing the concentration of adenosine 3′,5′-monophosphate within the tissue8. The cyclic-AMP is presumed to be the intracellular mediator of the vasopressin effect. Theophylline mimics vasopressin in toad bladder, since it inhibits the degradation of cyclic-AMP to inactive 5′-adenosine monophosphate9.

Joseph S. Handler

Papers

The similarity of effects of vasopressin, adenosine-3′,5′-phosphate (cyclic amp) and theophylline on the toad bladder

The role of adenosine 3′,5′-phosphate in the action of antidiuretic hormone

Membrane asymmetry in epithelia: is the tight junction a barrier to diffusion in the plasma membrane?

Effect of prostaglandin (pge-1) on the permeability response of toad bladder to vasopressin, theophylline and adenosine 3',5'-monophosphate.

The effect of vasopressin and of theophylline on the concentration of adenosine 3',5'-phosphate in the urinary bladder of the toad.