https://proteopedia.org/api.php?action=feedcontributions&feedformat=atom&user=Jacob+DotsonProteopedia - User contributions [en]2026-09-15T22:46:21ZUser contributionsMediaWiki 1.43.8https://proteopedia.org/index.php?title=Glucokinase_Regulatory_Protein&diff=1876350Glucokinase Regulatory Protein2013-12-16T04:37:41Z<p>Jacob Dotson: New page: <Structure load='4BB9' size='400' frame='true' align='right' caption='Glucokinase Regulatory Protein 4BB9 bound to fructose 1-phosphate, which deactivates the protein.' scene='Insert o...</p>
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<div><Structure load='4BB9' size='400' frame='true' align='right' caption='Glucokinase Regulatory Protein [[4BB9]] bound to fructose 1-phosphate, which deactivates the protein.' scene='Insert optional scene name here' /><br />
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== Glucokinase (Hexokinase 4) Regulatory Protein ==<br />
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Glucokinase regulatory protein is also known as glucokinase (hexokinase 4) regulator. This protein is important in the metabolism of glucose in the body. It maintains the location and activity of the enzyme glucokinase (hexokinase 4). Regulation occurs through competitive inhibition of glucokinase. The regulating protein binds to glucokinase, thus inhibiting glucokinase's activity. The regulatory protein is not present in the liver, where it's substrate is bio-synthesized.<ref>PMID: 7821739 </ref> Conversely, the regulatory protein is present in liver cells where glucokinase is synthesized.<br />
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Mutations in glucokinase regulatory protein can contribute to type 2 diabetes and hyperinsulinemic hypoglycemia. Both of these health issues involve either high or low levels of blood glucose.<ref>PMID: 10456334</ref><br />
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== Glucokinase Regulatory Protein Structure ==<br />
This protein is made up of 626 amino acids, and it weighs 68 kDa.<ref>PMID:2917560</ref> This protein is trilobal, with two identical sugar isomerase (SIS) domains <scene name='56/560866/Sis-1_and_sis-2/1'>(SIS-1 is in red and SIS-2 is in blue)</scene>, and one <scene name='56/560866/C-lid_domain/2'>alpha-helical c-terminal lid domain</scene>. The sugar isomerase domains are dominated by 5 stranded parallel beta-sheets that are flanked on either side by alpha-helices, Effectively making an <scene name='56/560866/Aba_motif/1'>alpha-beta-alpha motif</scene>. <br />
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The lid domain consists of seven alpha-helices, with a triple helical core. The core is flanked by a single helix that runs parallel to the triple helix. The remaining helices run perpendicular to the triple helix. There are 14 residues that act as links between the domains.<ref name="structure">PMID: 23621087 </ref><br />
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== Regulation Mechanism ==<br />
In the presence of fructose 6-phosphate, glucokinase regulatory protein is activated and releases the enzyme glucokinase. Fructose 6-phosphate is produced when glucose is present in concentrations higher than will be immediately digested. The regulatory protein is also antagonized by <scene name='56/560866/Zoomfruc6phos/1'>fructose 1-phosphate</scene>. In essence, the regulatory protein is activated when glucose is ready to be stored, and inactivated when the storage process is complete. <ref>PMID:18199594</ref><br />
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Gluokinase regulatory protein controls the location of glucokinase, which is important in the digestion of glucose. The enzyme phosphorylates glucose, in preparation for storage in the form of glycogen.<ref name="structure" /><ref>PMID:17353190</ref><br />
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== References ==<br />
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<references/></div>Jacob Dotson