Efficient Signal Transduction Research Articles

Magnetically modified bacteriophage-triggered ATP release activated EXPAR-CRISPR/Cas14a system for visual detection of Burkholderia pseudomallei

Burkholderia pseudomallei, widely distributed in tropical and subtropical ecosystems, is capable of causing the fatal zoonotic disease melioidosis and exhibiting a global trend of dissemination. Rapid and sensitive detection of B. pseudomallei is essential for environmental monitoring as well as infection control. Here, we developed an innovative biosensor for quantitatively detecting B. pseudomallei relies on ATP released triggered by bacteriophage-induced bacteria lysis. The lytic bacteriophage vB_BpP_HN01, with high specificity, is employed alongside magnetic nanoparticles assembly to create a biological receptor, facilitating the capture and enrichment of viable target bacteria. Following a brief extraction and incubation process, the captured target undergoes rapid lysis to release contents including ATP. The EXPAR-CRISPR cascade reaction provides an efficient signal transduction and dual amplification module that allowing the generated ATP to guide the signal output as an activator, ultimately converting the target bacterial amount into a detectable fluorescence signal. The proposed bacteriophage affinity strategy exhibited superior performance for B. pseudomallei detection with a dynamic range from 10^2 to 10^7 CFU mL−1, and a LOD of 45 CFU mL−1 within 80 min. Moreover, with the output signal compatible across various monitoring methods, this work offers a robust assurance for rapid diagnosis and on-site environmental monitoring of B. pseudomallei.

A Controlled Release Aptasensor Utilizing AIE-Active MOFs as High-Efficiency ECL Nanoprobe for the Sensitive Detection of Adenosine Triphosphate.

Improving the sensitivity in electrochemiluminescence (ECL) detection systems necessitates the integration of robust ECL luminophores and efficient signal transduction. In this study, we report a novel ECL nanoprobe (Zr-MOF) that exhibits strong and stable emission by incorporating aggregation-induced emission ligands into Zr-based metal-organic frameworks (MOFs). Meanwhile, we designed a high-performance signal modulator through the implementation of a well-designed controlled release system with a self-on/off function. ZnS quantum dots (QDs) encapsulated within the cavities of aminated mesoporous silica nanoparticles (NH2-SiO2) serve as the ECL quenchers, while adenosine triphosphate (ATP) aptamers adsorbed on the surface of NH2-SiO2 through electrostatic interaction act as "gatekeepers." Based on the target-triggered ECL resonance energy transfer between Zr-MOF and ZnS QDs, we establish a coreactant-free ECL aptasensor for the sensitive detection of ATP, achieving an impressive low detection limit of 0.033 nM. This study not only demonstrates the successful combination of ECL with controlled release strategies but also opens new avenues for developing highly efficient MOFs-based ECL systems.

High-Q Trampoline Resonators from Strained Crystalline InGaP for Integrated Free-Space Optomechanics.

Nanomechanical resonators realized from tensile-strained materials reach ultralow mechanical dissipation in the kHz to MHz frequency range. Tensile-strained crystalline materials that are compatible with epitaxial growth of heterostructures would thereby at the same time allow realizing monolithic free-space optomechanical devices, which benefit from stability, ultrasmall mode volumes, and scalability. In our work, we demonstrate nanomechanical string and trampoline resonators made from tensile-strained InGaP, which is a crystalline material that is epitaxially grown on an AlGaAs heterostructure. We characterize the mechanical properties of suspended InGaP nanostrings, such as anisotropic stress, yield strength, and intrinsic quality factor. We find that the latter degrades over time. We reach mechanical quality factors surpassing 107 at room temperature with a Q·f product as high as 7 × 1011Hz with trampoline-shaped resonators. The trampoline is patterned with a photonic crystal to engineer its out-of-plane reflectivity, desired for efficient signal transduction of mechanical motion to light.

Promoting the Differentiation of Neural Progenitor Cells into Oligodendrocytes through the Induction of Olig2 Expression: A Transcriptomic Study Using RNA-seq Analysis.

Oligodendrocytes are the myelinating cells of the central nervous system that facilitate efficient signal transduction. The loss of these cells and the associated myelin sheath can lead to profound functional deficits. Moreover, oligodendrocytes also play key roles in mediating glial-neuronal interactions, which further speaks to their importance in health and disease. Neural progenitor cells (NPCs) are a promising source of cells for the treatment of oligodendrocyte-related neurological diseases due to their ability to differentiate into a variety of cell types, including oligodendrocytes. However, the efficiency of oligodendrocyte differentiation is often low. In this study, we induced the expression of the Olig2 transcription factor in tripotent NPCs using a doxycycline-inducible promoter, such that the extent of oligodendrocyte differentiation could be carefully regulated. We characterized the differentiation profile and the transcriptome of these inducible oligodendrogenic NPCs (ioNPCs) using a combination of qRT-PCR, immunocytochemistry and RNA sequencing with gene ontology (GO) and gene set enrichment analysis (GSEA). Our results show that the ioNPCs differentiated into a significantly greater proportion of oligodendrocytes than the NPCs. The induction of Olig2 expression was also associated with the upregulation of genes involved in oligodendrocyte development and function, as well as the downregulation of genes involved in other cell lineages. The GO and GSEA analyses further corroborated the oligodendrocyte specification of the ioNPCs.

The roles of brain lipids and polar metabolites in the hypoxia tolerance of deep-diving pinnipeds.

Lipids make up more than half of the human brain's dry weight, yet the composition and function of the brain lipidome is not well characterized. Lipids not only provide the structural basis of cell membranes, but also take part in a wide variety of biochemical processes. In neurodegenerative diseases, lipids can facilitate neuroprotection and serve as diagnostic biomarkers. The study of organisms adapted to extreme environments may prove particularly valuable in understanding mechanisms that protect against stressful conditions and prevent neurodegeneration. The brain of the hooded seal (Cystophora cristata) exhibits a remarkable tolerance to low tissue oxygen levels (hypoxia). While neurons of most terrestrial mammals suffer irreversible damage after only short periods of hypoxia, in vitro experiments show that neurons of the hooded seal display prolonged functional integrity even in severe hypoxia. How the brain lipidome contributes to the hypoxia tolerance of marine mammals has been poorly studied. We performed an untargeted lipidomics analysis, which revealed that lipid species are significantly modulated in marine mammals compared with non-diving mammals. Increased levels of sphingomyelin species may have important implications for efficient signal transduction in the seal brain. Substrate assays also revealed elevated normoxic tissue levels of glucose and lactate, which suggests an enhanced glycolytic capacity. Additionally, concentrations of the neurotransmitters glutamate and glutamine were decreased, which may indicate reduced excitatory synaptic signaling in marine mammals. Analysis of hypoxia-exposed brain tissue suggests that these represent constitutive mechanisms rather than an induced response towards hypoxic conditions.

Neurotransmitters in Type 2 Diabetes and the Control of Systemic and Central Energy Balance.

Efficient signal transduction is important in maintaining the function of the nervous system across tissues. An intact neurotransmission process can regulate energy balance through proper communication between neurons and peripheral organs. This ensures that the right neural circuits are activated in the brain to modulate cellular energy homeostasis and systemic metabolic function. Alterations in neurotransmitters secretion can lead to imbalances in appetite, glucose metabolism, sleep, and thermogenesis. Dysregulation in dietary intake is also associated with disruption in neurotransmission and can trigger the onset of type 2 diabetes (T2D) and obesity. In this review, we highlight the various roles of neurotransmitters in regulating energy balance at the systemic level and in the central nervous system. We also address the link between neurotransmission imbalance and the development of T2D as well as perspectives across the fields of neuroscience and metabolism research.

Molecularly Hybridized Conduction in DPP-Based Donor-Acceptor Copolymers toward High-Performance Iono-Electronics.

Iono-electronics, that is, transducing devices able to translate ionic injection into electrical output, continue to demand a variety of mixed ionic-electronic conductors (MIECs). Though polar sidechains are widely used in designing novel polymer MIECs, it remains unclear to chemists how much balance is needed between the two antagonistic modes of transport (ion permeability and electronic charge transport) to yield high-performance materials. Here, the impact of molecularly hybridizing ion permeability and charge mobility in semiconducting polymers on their performance in electrochemical and synaptic transistors is investigated. A series of diketopyrrolopyrrole (DPP)-based copolymers are employed to demonstrate the multifunctionality attained by controlling the density of polar sidechains along the backbone. Notably, efficient electrochemical signal transduction and reliable synaptic plasticity are demonstrated via controlled ion insertion and retention. The newly designed DPP-based copolymers further demonstrate unprecedented thermal tolerance among organic mixed ionic-electronic conductors, a key property in the manufacturing of organic electronics.

TLR3 forms a laterally aligned multimeric complex along double-stranded RNA for efficient signal transduction

Toll-like receptor 3 (TLR3) is a member of the TLR family, which plays an important role in the innate immune system and is responsible for recognizing viral double-stranded RNA (dsRNA). Previous biochemical and structural studies have revealed that a minimum length of approximately 40–50 base pairs of dsRNA is necessary for TLR3 binding and dimerization. However, efficient TLR3 activation requires longer dsRNA and the molecular mechanism underlying its dsRNA length-dependent activation remains unknown. Here, we report cryo-electron microscopy analyses of TLR3 complexed with longer dsRNA. TLR3 dimers laterally form a higher multimeric complex along dsRNA, providing the basis for cooperative binding and efficient signal transduction.

CRISPR/Cas Precisely Regulated DNA-Templated Silver Nanocluster Fluorescence Sensor for Meat Adulteration Detection.

Meat adulteration can cause consumer fraud, food allergies, and religious issues. Rapid and sensitive detection methods are urgently demanded to supervise meat authenticity. Herein, a clustered regularly interspaced short palindromic repeats (CRISPR)/Cas precisely regulated DNA-templated silver nanocluster (DNA-AgNC) sensor was ingeniously designed to detect meat adulteration. Specific sequence recognition of CRISPR/Cas12a allowed accurate identification of target DNA. The emerging label-free fluorescent probes, DNA-AgNCs, a class of promising fluorophores in biochemical analysis with attractive photostability and remarkably enhanced fluorescence properties, were first introduced as the substrates of CRISPR/Cas12a system, allowing a sensitive output of amplified signals through the precise regulation of the unique target DNA-activated trans-cleavage activity of Cas12a. Based on this specific recognition, efficient signal transduction of CRISPR/Cas12a, and the outstanding fluorescence properties of DNA-AgNCs, the proposed strategy achieved a satisfactory linear range from 10 pM to 1 μM with a limit of detection (LOD) as low as 1.9 pM, which can achieve sensitive detection of meat adulteration.

The Railmap of Type I Interferon Induction: Subcellular Network Plan and How Viruses Can Change Tracks.

The innate immune response constitutes the cell’s first line of defense against viruses and culminates in the expression of type I interferon (IFN) and IFN-stimulated genes, inducing an antiviral state in infected and neighboring cells. Efficient signal transduction is a key factor for strong but controlled type I IFN expression and depends on the compartmentalization of different steps of the signaling cascade and dynamic events between the involved compartments or organelles. This compartmentalization of the innate immune players not only relies on their association with membranous organelles but also includes the formation of supramolecular organizing centers (SMOCs) and effector concentration by liquid–liquid phase separation. For their successful replication, viruses need to evade innate defenses and evolve a multitude of strategies to impair type I IFN induction, one of which is the disruption of spatial immune signaling dynamics. This review focuses on the role of compartmentalization in ensuring an adequate innate immune response to viral pathogens, drawing attention to crucial translocation events occurring downstream of pattern recognition and leading to the expression of type I IFN. Furthermore, it intends to highlight concise examples of viral countermeasures interfering with this spatial organization to alleviate the innate immune response.

Ku proteins promote DNA binding and condensation of cyclic GMP-AMP synthase.

Cyclic GMP-AMP synthase (cGAS) is a cytosolic DNA sensor that plays a critical role in regulating antiviral signaling. cGAS binds to DNA and catalyzes the synthesis of cyclic GMP-AMP (cGAMP), which is essential for downstream signal transduction. The antiviral response is a rapid biological process; however, cGAS itself has relatively low DNA binding affinity, implying that formation of the cGAS-DNA complex requires an additional factor(s) that promotes cGAS-DNA binding, allowing efficient antiviral signal transduction. Here, we report that the Ku proteins (Ku80 and Ku70) directly interact with cGAS and positively regulate cGAS-mediated antiviral signaling. Mechanistically, we find that the interaction of the Ku proteins with cGAS significantly increases the DNA-binding affinity of cGAS and promotes cGAS condensation in the cytosol, thereby enhancing cGAS catalytic activity. Our results show that the Ku proteins are critical partners of cGAS in sensing DNA virus infection and ensuring efficient innate immune signal transduction.

Electrochemical Profiling of Plants

The profiling, or fingerprinting, of distinct varieties of the Plantae kingdom is based on the bioactive ingredients, which are systematically segregated to perform their detailed analysis. The secondary products portray a pivotal role in defining the ecophysiology of distinct plant species. There is a crucial role of the profiling domain in understanding the various features, characteristics, and conditions related to plants. Advancements in variable technologies have contributed to the development of highly specific sensors for the non-invasive detection of molecules. Furthermore, many hyphenated techniques have led to the development of highly specific integrated systems that allow multiplexed detection, such as high-performance liquid chromatography, gas chromatography, etc., which are quite cumbersome and un-economical. In contrast, electrochemical sensors are a promising alternative which are capable of performing the precise recognition of compounds due to efficient signal transduction. However, due to a few bottlenecks in understanding the principles and non-redox features of minimal metabolites, the area has not been explored. This review article provides an insight to the electrochemical basis of plants in comparison with other traditional approaches and with necessary positive and negative outlooks. Studies consisting of the idea of merging the fields are limited; hence, relevant non-phytochemical reports are included for a better comparison of reports to broaden the scope of this work.

Proximity-field nanopatterning for high-performance chemical and mechanical sensor applications based on 3D nanostructures

In this era of the Internet of Things, the development of innovative sensors has rapidly accelerated with that of nanotechnology to accommodate various demands for smart applications. The practical use of three-dimensional (3D) nanostructured materials breaks several limitations of conventional sensors, including the large surface-to-volume ratio, precisely tunable pore size and porosity, and efficient signal transduction of 3D geometries. This review provides an in-depth discussion on recent advances in chemical and mechanical sensors based on 3D nanostructures, which are rationally designed and manufactured by advanced 3D nanofabrication techniques that consider structural factors (e.g., porosity, periodicity, and connectivity). In particular, we focus on a proximity-field nanopatterning technique that specializes in the production of periodic porous 3D nanostructures that satisfy the structural properties universally required to improve the performance of various sensor systems. State-of-the-art demonstrations of high-performance sensor devices such as supersensitive gas sensors and wearable strain sensors realized through designed 3D nanostructures are summarized. Finally, challenges and outlooks related to nanostructures and nanofabrication for the practical application of 3D nanostructure-based sensor systems are proposed.

Structural and Functional Coupling of Calcium-Activated BK Channels and Calcium-Permeable Channels Within Nanodomain Signaling Complexes.

Biochemical and functional studies of ion channels have shown that many of these integral membrane proteins form macromolecular signaling complexes by physically associating with many other proteins. These macromolecular signaling complexes ensure specificity and proper rates of signal transduction. The large-conductance, Ca2+-activated K+ (BK) channel is dually activated by membrane depolarization and increases in intracellular free Ca2+ ([Ca2+]i). The activation of BK channels results in a large K+ efflux and, consequently, rapid membrane repolarization and closing of the voltage-dependent Ca2+-permeable channels to limit further increases in [Ca2+]i. Therefore, BK channel-mediated K+ signaling is a negative feedback regulator of both membrane potential and [Ca2+]i and plays important roles in many physiological processes and diseases. However, the BK channel formed by the pore-forming and voltage- and Ca2+-sensing α subunit alone requires high [Ca2+]i levels for channel activation under physiological voltage conditions. Thus, most native BK channels are believed to co-localize with Ca2+-permeable channels within nanodomains (a few tens of nanometers in distance) to detect high levels of [Ca2+]i around the open pores of Ca2+-permeable channels. Over the last two decades, advancement in research on the BK channel’s coupling with Ca2+-permeable channels including recent reports involving NMDA receptors demonstrate exemplary models of nanodomain structural and functional coupling among ion channels for efficient signal transduction and negative feedback regulation. We hereby review our current understanding regarding the structural and functional coupling of BK channels with different Ca2+-permeable channels.

Rapid SARS-CoV-2 Nucleic Acid Testing and Pooled Assay by Tetrahedral DNA Nanostructure Transistor.

Direct SARS-CoV-2 nucleic acid testing with fast speed and high frequency is crucial for controlling the COVID-19 pandemic. Here, direct testing of SARS-CoV-2 nucleic acid is realized by field-effect transistors (FETs) with an electro-enrichable liquid gate (LG) anchored by tetrahedral DNA nanostructures (TDNs). The applied gate bias electrostatically preconcentrates nucleic acids, while the liquid gate with TDNs provides efficient analyte recognition and signal transduction. The average diagnosis time is ∼80 s, and the limit of detection approaches 1-2 copies in 100 μL of clinical samples without nucleic acid extraction and amplification. As such, TDN-LG FETs solve the dilemma of COVID-19 testing on mass scale that diagnosis accuracy and speed undergo trade-off. In addition, TDN-LG FETs achieve unamplified 10-in-1 pooled nucleic acid testing for the first time, and the results are consistent with PCR. Thus, this technology promises on-site and wide population COVID-19 screening and ensures safe world-reopening.

Photoreaction of photoactivated adenylate cyclase from cyanobacterium Microcoleus chthonoplastes.

The photochemical reaction of photoactivated adenylate cyclase from cyanobacterium Microcoleus chthonoplastes PCC 7420 (mPAC), which consists of a Per-Arnt-Sim (PAS), a light‑oxygene-voltage (LOV), and an adenylate cyclase (AC) domain, was investigated mainly using the time-resolved transient grating method. An absorption spectral change associated with an adduct formation between its chromophore (flavin mononucleotide) and a cysteine residue was observed with a time constant of 0.66μs. After this reaction, a significant diffusion coefficient (D)-change was observed with a time constant of 38ms. The determined D-value was concentration-dependent indicating a rapid equilibrium between the dimer and tetramer. Combining the results of size exclusion chromatography and CD spectroscopy, we concluded that the photoinduced D-change was mainly attributed to the equilibrium shift from the dimer rich to the tetramer rich states upon light exposure. Since the reaction rate does not depend on concentration, the rate determining step of the tetramer formation is not the collision of proteins by diffusion, but a conformation change. The roles of the PAS and AC domains as well as the N- and C-terminal flanking helices of the LOV domain (A'α- and Jα-helices) were investigated using various truncated mutants. The PAS domain was found to be a strong dimerization site and is related to efficient signal transduction. It was found that simultaneous existence of the A'α- and Jα-helices in mPAC is important for the light-induced conformation change to lead the conformation change which induces the tetramer formation. The results suggest that the angle changes of the coiled-coil structures in the A'α and Jα-helices are essential for this conformation change. The reaction scheme of mPAC is proposed.

GH Receptor Exon 3 Genotype and Echocardiographic Abnormalities in Patients With Active Acromegaly

Background: The GH receptor (GHR) exon 3 polymorphism occurs at a genomic level. Approximately 50-60% of the population is homozygous for the exon-3 containing genotype (+3/+3), 30-40% are heterozygous (+3/-3) and 10-20% are homozygous for the exon-3 lacking genotype (-3/-3). Some studies suggest that children homo- and heterozygous for the GHR exon 3 lacking genotype (-more efficient 3/-3 and +3/-3, respectively) respond better to treatment with exogenous rhGH and there is also in vitro evidence showing a more efficient signal transduction through this exon 3 deleted isoform. Some studies have found that patients with acromegaly harboring the exon 3-deleted genotype may have a higher prevalence of diabetes and hypertension. Hypothesis and Objective: Patients with active acromegaly harboring the exon 3-lacking GHR genotype may have more echocardiographic abnormalities than those who are homozygous for the exon 3 containing genotype. Patients and Methods: This is a cross-sectional study of patients with active acromegaly, defined by an IGF-1 level > 1.3 times the upper limit of normal (x ULN), who underwent transthoracic echocardiography. Exon-3 GHR genotype was determined by PCR using previously described sense and antisense primers. Results: The cohort consisted of 28 patients, 54% female, with a mean age of 51 ± 12 years. Mean disease duration at the time of echocardiographic examination was 4.48 ± 4.7 years; median basal GH and IGF-1 were 12 ± 26 ng/mL and 2.4 ± 1.04 x ULN. The prevalence of hypertension and diabetes were 43% and 36%, respectively. Fifty three percent of the patients were homozygous for the exon 3-containaing genotype (+3/+3), 18% were homozygous for the exon 3-lacking genotype (-3/-3) and 29% were heterozygous (+3/-3). Clinical and biochemical features did not differ between patients with the different GHR genotypes, except for hypertension that was more prevalent in the +3/+3 genotype group (60% vs 23%, p= 0.04). The frequency of the different echocardiographic parameters was similar among groups (left ventricular hypertrophy 33% vs 15%, p= 0.27; diastolic dysfunction 47% vs 31%, p= 0.39; subclinical systolic dysfunction 42% vs 54%, p= 0.54; left ventricular ejection fraction 59±10% vs 60±16%, p= 0.83); aortic valve abnormalities 19% vs 15%, p=0.63; mitral valve abnormalities 46% vs 15%, p=0.07). Conclusions: Echocardiographic abnormalities in patients with active acromegaly do not differ among patients with the different GHR exon 3 genotypes. The clinical spectrum of acromegaly varies considerably. Although such variability is usually related to the severity of the hypersomatotropinemia, in many patients this is not the case.

Multiplexed detection of bacterial pathogens based on a cocktail of dual-modified phages

Rapid, quantitative, and sensitive assays for the multiplexed detection of bacterial pathogens are urgently needed for public health. Here, we report the generation of dual-modified phage sensors for the simultaneous detection of multiple pathogenic bacteria. The M13KE phage was dual modified to display the targeting peptide on the minor coat protein pIII (∼5 copies) and the streptavidin-binding (StrB) peptide on the major coat protein pVIII (∼2700 copies). The targeting peptide specifically recognizes the target bacteria, and the StrB peptide acts as the efficient signal amplification and transduction unit upon binding with fluorescently tagged streptavidin. The bright fluorescence emitted from individual target bacteria can be clearly distinguished from the background via both the flow cytometry and fluorescence microscopy. Three different dual-modified phages targeting E. coli O157:H7, Salmonella Typhimurium, and Pseudomonas aeruginosa were constructed, and high specificity was verified via a large excess of other non-target bacteria. Using a 40 mL sample volume, the target bacteria detection limit was approximately 102 cells/mL via flow cytometry measurement in the presence of other non-target bacteria. By combining these three dual-modified phages into a cocktail, simultaneous detection and quantification of three target bacterial pathogens was demonstrated with good linearity. The strategy of constructing dual-modified phage represents a promising tool in the detection of bacterial pathogens.

Blood-Brain Barrier and Neurovascular Unit In Vitro Models for Studying Mitochondria-Driven Molecular Mechanisms of Neurodegeneration.

Pathophysiology of chronic neurodegeneration is mainly based on complex mechanisms related to aberrant signal transduction, excitation/inhibition imbalance, excitotoxicity, synaptic dysfunction, oxidative stress, proteotoxicity and protein misfolding, local insulin resistance and metabolic dysfunction, excessive cell death, development of glia-supported neuroinflammation, and failure of neurogenesis. These mechanisms tightly associate with dramatic alterations in the structure and activity of the neurovascular unit (NVU) and the blood–brain barrier (BBB). NVU is an ensemble of brain cells (brain microvessel endothelial cells (BMECs), astrocytes, pericytes, neurons, and microglia) serving for the adjustment of cell-to-cell interactions, metabolic coupling, local microcirculation, and neuronal excitability to the actual needs of the brain. The part of the NVU known as a BBB controls selective access of endogenous and exogenous molecules to the brain tissue and efflux of metabolites to the blood, thereby providing maintenance of brain chemical homeostasis critical for efficient signal transduction and brain plasticity. In Alzheimer’s disease, mitochondria are the target organelles for amyloid-induced neurodegeneration and alterations in NVU metabolic coupling or BBB breakdown. In this review we discuss understandings on mitochondria-driven NVU and BBB dysfunction, and how it might be studied in current and prospective NVU/BBB in vitro models for finding new approaches for the efficient pharmacotherapy of Alzheimer’s disease.

Every Detail Matters. That Is, How the Interaction between Gα Proteins and Membrane Affects Their Function.

In highly organized multicellular organisms such as humans, the functions of an individual cell are dependent on signal transduction through G protein-coupled receptors (GPCRs) and subsequently heterotrimeric G proteins. As most of the elements belonging to the signal transduction system are bound to lipid membranes, researchers are showing increasing interest in studying the accompanying protein–lipid interactions, which have been demonstrated to not only provide the environment but also regulate proper and efficient signal transduction. The mode of interaction between the cell membrane and G proteins is well known. Despite this, the recognition mechanisms at the molecular level and how the individual G protein-membrane attachment signals are interrelated in the process of the complex control of membrane targeting of G proteins remain unelucidated. This review focuses on the mechanisms by which mammalian Gα subunits of G proteins interact with lipids and the factors responsible for the specificity of membrane association. We summarize recent data on how these signaling proteins are precisely targeted to a specific site in the membrane region by introducing well-defined modifications as well as through the presence of polybasic regions within these proteins and interactions with other components of the heterocomplex.