University of Louisville researchers are one step closer to helping millions of people whose salivary glands no longer work because of disease or damage from treatment of diseases.
The scientific finding of Douglas Darling, PhD, professor, Department of Oral Health and Rehabilitation, UofL School of Dentistry, and his team identified a protein sorting mechanism used by the salivary gland. The National Institutes of Health supported study published on-line first this week in the Journal of Dental Research.
The scientific discovery could form the basis for advanced therapies for patients whose salivary glands are damaged or no longer function due to radiation therapy, prescription drugs or Sjogren's Syndrome – an immune system disorder often defined by its two most common symptoms — dry eyes and a dry mouth.
The salivary glands are essential for lubrication, defense and beginning digestion in the mouth. The largest of the salivary glands - the parotid - secretes important proteins into the saliva. As with all salivary glands, it has multiple secretion pathways, therefore it must sort proteins destined for saliva into the correct pathway for secretion. This can be tricky as there are seven possible pathways. One pathway takes proteins to the salivary duct, other pathways carry different proteins to the 'back' side of the cell to be secreted into the blood or to form a supportive matrix for the cells. Transport along these pathways occurs by sorting the proteins into vesicles (hollow membrane sacs) that carry their "cargo" to the correct destination.
Conventional thought was that cargo proteins are moved into the forming vesicles by attaching to sorting receptor proteins. Darling and his team have discovered a completely new approach, suggesting the reason no salivary sorting receptor protein has been found is that it may not exist.
In Darling's new model, the salivary cargo protein, Parotid Secretory Protein (PSP), selectively and directly binds to a rare lipid, a type of fat molecule called PtdIns(3,4)P2, present only in certain cell membranes - and only present on one side of the membrane. Darling also found PtdIns(3,4)P2 can flip to the inner part of the vesicle membrane –giving PSP the opportunity to bind it.
"These data imply that phosphatidylinositol-phosphate lipids like PtdIns(3,4)P2 may have multiple functions on the inner surface of organelles," Darling said. "This is contrary to the current belief that their functions are always limited to one surface of the cell membrane."
The next step is for Darling and his team to identify the molecular components used for flipping PtdIns(3,4)P2, and develop approaches to test ways to manipulate this potential protein sorting mechanism.
The study, Parotid Secretory Protein Binds Phosphatidylinositol (3,4) Bisphosphate can be found on the Journal of Dental Research website.
Julie Heflin | EurekAlert!
Study suggests possible new target for treating and preventing Alzheimer's
02.12.2016 | Oregon Health & Science University
The first analysis of Ewing's sarcoma methyloma opens doors to new treatments
01.12.2016 | IDIBELL-Bellvitge Biomedical Research Institute
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy