<span>Lafora disease is the most severe teenage-onset progressive epilepsy, a unique form of glycogenosis with perikaryal accumulation of an abnormal form of glycogen, and a neurodegenerative disorder exhibiting an unusual generalized organellar disintegration. The disease is caused by mutations of the EPM2A gene, which encodes two isoforms of the laforin protein tyrosine phosphatase, having alternate carboxyl termini, one localized in the cytoplasm (endoplasmic reticulum) and the other in the nucleus. To date, all documented disease mutations, including the knockout mouse model deletion, have been in the segment of the protein common to both isoforms. It is therefore not known whether dysfunction of the cytoplasmic, nuclear, or both isoforms leads to the disease. In the present work, we identify six novel mutations, one of which, c.950insT (Q319fs), is the first mutation specific to the cytoplasmic laforin isoform, implicating this isoform in disease pathogenesis. To confirm this mutation's deleterious effect on laforin, we studied the resultant protein's subcellular localization and function and show a drastic reduction in its phosphatase activity, despite maintenance of its location at the endoplasmic reticulum.
I got my information from </span>https://www.ncbi.nlm.nih.gov/pubmed/14722920
Complete question:
The endplate potential (EPP) at the frog neuromuscular junction occurs because ACh simultaneously increases the conductance of the postsynaptic membrane to Na and K
Answer:
TRUE
Explanation:
The Acetylcholine neurotransmitter is released from the presynaptic cell by the process of exocytosis.
Once the molecule is in the intercellular space, it moves forward the postsynaptic membrane to join its receptor in the motor plate.
Once the joining has occurred, the receptor acquires a channel shape allowing the ion transference that will make possible the modification of the action potential. Ions traffic will consist of the pass of sodium and calcium to the interior of the cell and potassium to the exterior. Quantitatively, the interchange Na-K is the most significant.
K+ follows a concentration gradient, while Na+ follows an electrochemical gradient. The interchange results in an increase of positive charges in the interior of the muscular cell.
Whenever there is a sufficient number of Acetylcholine receptors are active, the depolarization threshold of the motor endplate is exceeded. This activates an action potential that extends to the rest of the muscle membrane.
In the brain especially in the eyes
The immune system helps neutralize disease and infection. The digestive system processes nutrients from food. The skeletal system includes your bones and supports and protects your body. The correct answer is the nervous system.
Answer:
an enzyme produced chiefly by certain bacteria, having the property of cleaving DNA molecules at or near a specific sequence of bases.
