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Gene & Protein in Disease β-cell regeneration and stem cell niche

may be used to modify pathways, such as manipulating messengers. However, fura-2-based fluorescence imaging
Wnt signaling, p21, and homeobox protein Hox-B4. 58 revealed calcium signals within intact pancreatic islets
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Membrane proteins known as GPCRs can detect a when arginine vasopressin or ghrelin was applied. The
wide range of signals, including photons, ions, proteins, methodology enabled the measurement of intracellular
neurotransmitters, and hormones. The GPCR superfamily cyclic adenosine monophosphate (cAMP) levels caused by
is divided into five subfamilies: glutamate, frizzled/taste2, receptors linked to Gs and Gi/o proteins, allowing for an
accurate assessment of GPCR activity in intact islets. The
rhodopsin, adhesion, and secretin receptors. Abnormalities second messengers IP1, cAMP, and calcium can be detected,
in ligand concentration, GPCR protein expression, or
mutations are implicated in numerous pathophysiological thus enhancing our understanding of their diverse effects
conditions, including diseases of the gastrointestinal on cellular function. Continuous investigation into ligand-
system, central nervous system, respiratory system, receptor interactions, conformational analyses, effector-
musculoskeletal pathologies, cardiovascular and metabolic receptor engagement, and signaling patterns should lead
systems, immune diseases, and eye disorders. GPCRs to new approaches for developing novel therapeutics.
account for 30% of all recognized pharmacological targets, The G protein-coupled estrogen receptor (GPER) and its
potential involvement in illness development and disease
making them central to the development of innovative treatment are currently under research. GPER binding
drugs and a common therapeutic intervention strategy. mediates a number of activities, including metabolic flaws
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However, a significant challenge persists: integrating and insulin resistance, as suggested by in vivo research.
extrinsic and intrinsic regulatory fate determinants through
the main signaling channels into cohesive networks of The treatment of T2D and obesity often involves the
regulatory systems. This understanding could lead to use of glucagon-like peptide-1 receptor (GLP-1R) agonists,
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novel methods for preserving and boosting HSCs in vitro. which enhance pancreatic cell activity and increase insulin
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Interestingly, the molecular mechanisms for managing and sensitivity by promoting weight loss. These agonists are
maintaining plant stem cells show similarities to those in synthetic analogs of naturally occurring agonists such as
animals. GLP-1(7-36) NH or its paralogue exendin-4, modified
2
to possess longer pharmacokinetic half-lives. Current
Furthermore, this section covers the most recent
research on the genetic control of signaling in plant research has demonstrated that altering the amino acid
sequence of orthosteric GLP-1R peptide agonists can
meristems. It begins with providing guidance on the significantly change their intracellular signaling profiles,
regulation of the shoot and root apical meristems. The resulting in decreased coupling to intracellular effectors.
borders between plant stem cells and their developing This imbalance, favoring G protein-dependent signaling,
progeny are maintained through transcriptional and is frequently referred to as “bias.” In the initial stages
posttranscriptional regulation. A graphic representation of diabetes, there is a disruption in the initial phase of
of the roles of signaling molecules, such as the hormones insulin production, followed by a gradual decline in
auxin and cytokines, is provided (Figure 10). Another the glucose’s capacity to stimulate insulin secretion. To
aspect of control is documented in lateral meristems, where develop therapeutic interventions aimed at altering insulin
numerous crucial regulators of stem cell maintenance secretory activity and/or cell mass, a better knowledge
show unexpected parallels to those in apical meristems. of the signaling pathways associated with the activation
The regulation of grass rhizomes is also discussed, as many of GPCRs and their interactions within cells is essential.
agricultural plants fall into this category. The reproductive Gi-GPCRs, with interact with G proteins of the i/o class,
success of these plants, and consequently their agronomic play a role in regulating a variety of cellular activities
yield, depends greatly on shoot architecture. Therefore, in mammalian tissues, but their influence on tissue
topics such as phyllotaxy, leaf initiation patterning, and development and expansion is less apparent. This article
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floral induction are covered, given their importance for covers recent findings on GPCRs functionally expressed
members of the grass family. A brief presentation on the in β-cells, which have important properties for the
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relevant genetic and hormonal regulation is presented. development of T2D therapies. While pancreatic islet cells
The study investigated second messenger activation in express GPCRs, their specific roles remain unclear. A study
mouse pancreatic islets, which regulate glucose-induced identified specific GPCRs, such as free fatty acid receptor 4
insulin release. It was found that activating Gq/11-coupled (FFAR4), prostaglandin E receptor 4 (PTGER4), purinergic
receptors in primary cells increased second messenger receptor (P2RY14), adrenoceptor beta 2 (ADRB2), and
IP1, but this signal was eliminated when a Gq/11 protein G-protein coupled receptor 54 (GPR54, also identified
inhibitor was used. Activation of V1 vasopressin and as KISS1R), located in primary cilia of both mouse and
ghrelin receptors did not significantly increase second human islet cells. These GPCRs stimulate ciliary cAMP
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Volume 3 Issue 2 (2024) 13 doi: 10.36922/gpd.2996