ABSTRACT
A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) -LC-MS/MS method was developed for the determination of hexachlorophene in fruits and vegetables. Samples were extracted by acetonitrile and then salted with an acetate buffer system. Extractants neutral alumina (Al-N), strong cation exchange silica gel bonded adsorbent (SCX) and graphitized carbon black (GCB) were used for sample purification. The method demonstrates excellent accuracy and reproducibility. Under optimized conditions, the correlation coefficients of hexachlorophene were higher than 0.995 in the range of 0.5-20 ng/mL. The limit of quantification (LOQ) was 2.0 µg/kg. The average recoveries, assessed at three spiked levels (2.0, 4.0, and 20.0µg/kg) across various matrices including cabbage, celery, tomato, eggplant, potato, radish, cowpea, chives, apple, peach, grape, citrus, bitter melon, banana and hami melon ranged from 72.0 to 100.5% with relative standard deviations from 3.2 to 9.8% (n = 6).
Subject(s)
Fruit , Pesticide Residues , Tandem Mass Spectrometry , Vegetables , Tandem Mass Spectrometry/methods , Vegetables/chemistry , Fruit/chemistry , Chromatography, High Pressure Liquid/methods , Pesticide Residues/analysis , Food Contamination/analysis , Reproducibility of Results , Limit of DetectionABSTRACT
Li-rich Mn-based cathode materials (LLOs) are often faced with problems such as low initial Coulombic efficiency (ICE), limited rate performance, voltage decay, and structural instability. Addressing these problems with a single approach is challenging. To overcome these limitations, we developed an LLO with surface functionalization using a simple fabrication method. This two-step process involved a liquid-stage NaBF4 treatment followed by an in situ chemical reaction during sintering. This reaction led to the creation of oxygen vacancies (OV), spinel structures, and doping with Na at the Li site, B at the tetrahedral interstitial spaces of O in both the transition-metal (TM) layer and Li layers as well as the octahedral interstices in the TM layer, and F at the O site. We have carried out a thorough study and employed density functional theory calculations to reveal the hidden mechanisms. The treatment not only increases the electrical conductivity but also changes the oxygen charge environment and inhibits lattice oxygen activity. Surprisingly, the B-O bond is so strong that it prevents the migration of TM within the tetrahedral interstitial spaces of O in both the TM and Li layers, hence stabilizing its structure. This bonding interaction strengthens the transition of the TM 3d and O 2p states to lower energy levels, thus causing an increase in the redox potentials. Hence, a rise in the operating voltage occurs. Of special importance, this therapy dramatically increases the ICE to 90.29% and keeps a specified capacity of 203.3 mAh/g after 100 cycles at 1C, which is an excellent capacity retention of 89.94%. This study introduces ideas and methods to tackle the challenges associated with LLOs in batteries. It also provides compelling evidence for the development of high-energy-density Li-ion batteries.
ABSTRACT
Spider silk exhibits an excellent combination of high strength and toughness, which originates from the hierarchical self-assembled structure of spidroin during fiber spinning. In this work, superfine nanofibrils are established in polyelectrolyte artificial spider silk by optimizing the flexibility of polymer chains, which exhibits combination of breaking strength and toughness ranging from 1.83 GPa and 238 MJ m-3 to 0.53 GPa and 700 MJ m-3, respectively. This is achieved by introducing ions to control the dissociation of polymer chains and evaporation-induced self-assembly under external stress. In addition, the artificial spider silk possesses thermally-driven supercontraction ability. This work provides inspiration for the design of high-performance fiber materials.
Subject(s)
Nanofibers , Polyelectrolytes , Silk , Spiders , Animals , Nanofibers/chemistry , Spiders/chemistry , Silk/chemistry , Polyelectrolytes/chemistry , Tensile Strength , Muscles , Biomimetic Materials/chemistryABSTRACT
The seat of human intelligence is the human cerebral cortex, which is responsible for our exceptional cognitive abilities. Identifying principles that lead to the development of the large-sized human cerebral cortex will shed light on what makes the human brain and species so special. The remarkable increase in the number of human cortical pyramidal neurons and the size of the human cerebral cortex is mainly because human cortical radial glial cells, primary neural stem cells in the cortex, generate cortical pyramidal neurons for more than 130 days, whereas the same process takes only about 7 days in mice. The molecular mechanisms underlying this difference are largely unknown. Here, we found that bone morphogenic protein 7 (BMP7) is expressed by increasing the number of cortical radial glial cells during mammalian evolution (mouse, ferret, monkey, and human). BMP7 expression in cortical radial glial cells promotes neurogenesis, inhibits gliogenesis, and thereby increases the length of the neurogenic period, whereas Sonic Hedgehog (SHH) signaling promotes cortical gliogenesis. We demonstrate that BMP7 signaling and SHH signaling mutually inhibit each other through regulation of GLI3 repressor formation. We propose that BMP7 drives the evolutionary expansion of the mammalian cortex by increasing the length of the neurogenic period.
Subject(s)
Ependymoglial Cells , Hedgehog Proteins , Animals , Mice , Humans , Ependymoglial Cells/metabolism , Hedgehog Proteins/metabolism , Ferrets/metabolism , Cerebral Cortex , Neurogenesis , Mammals/metabolism , Neuroglia/metabolism , Bone Morphogenetic Protein 7/metabolismABSTRACT
Lithium (Li) metal anodes are drawing considerable attention owing to their ultrahigh theoretical capacities and low electrochemical reduction potentials. However, their commercialization has been hampered by safety hazards induced by continuous dendrite growth. These issues can be alleviated using the ZnO-modified 3D carbon-based host containing carbon nanotubes (CNTs) and carbon felt (CF) fabricated by electroplating in the present study (denoted as ZnO/CNT@CF). The constructed skeleton has lithiophilic ZnO that is gradationally distributed along its thickness. The utilization of an inverted ZnO/CNT@CF-Li anode obtained by flipping over the carbon skeleton after Li electrodeposition is also reported herein. The synergistic effect of the Li metal and lithiophilic sites reduces the nucleation overpotential, thus inducing Li+ to preferentially deposit inside the porous carbon-based scaffold. The composite electrode compels Li to grow away from the separator, thereby significantly improving battery safety. A symmetric cell with the inverted ZnO/CNT@CF-Li electrode operates steadily for 700â cycles at 1â mA cm-2 and 1â mAh cm-2 . Moreover, the ZnO/CNT@CF-Li|S cell exhibits an initial areal capacity of 10.9â mAh cm-2 at a S loading of 10.4â mg cm-2 and maintains a capacity of 3.0â mAh cm-2 after 320â cycles.
ABSTRACT
Neurons exhibit excellent signal transmission capacity, which inspire artificial neuron materials for applications in the field of wearable electronics and soft robotics. In addition, the neuron fibers exhibit good mechanical robustness by sticking to the organs, which currently has rarely been studied. Here, a sticky artificial spider silk is developed by employing a proton donor-acceptor (PrDA) hydrogel fiber for application as artificial neuron fibers. Tuning the molecular electrostatic interactions by modulating the sequences of proton donors and acceptors, enables combination of excellent mechanical properties, stickiness, and ion conductivity. In addition, the PrDA hydrogel exhibits high spinning capacity for a wide range of donor-acceptor combinations. The PrDA artificial spider silk would shed light on the design of new generation of artificial neuron materials, bio-electrodes, and artificial synapses.
Subject(s)
Silk , Spiders , Animals , Protons , Electronics , HydrogelsABSTRACT
Owing to the strong energy advantage of lithium anodes, the development of lithium-metal batteries has become an inevitable trend. However, plagued by the instability of solid-electrolyte interphase (SEI) films, lithium metal anodes face challenges such as lithium dendrite formation and volume expansion. Studies have proven that modulating the composition and structure of SEI films by using electrolyte additives is a convenient and valid method. Currently, it is widely accepted that fluoride is an effective additive but, based on the high cost of fluoride production and environmental concerns, the development of fluoride-free additives is of great significance. In this work, the bifunctional additive N,O-bis(trimethylsilyl)acetamide (BSA) is proposed, which can build up a SEI layer that is rich in SiOx and Li3 N on the surface of the lithium anode to control the deposition behavior of lithium and clean the electrolyte of HF to protect the electrode. The experimental results indicate that BSA suppresses the generation of lithium dendrites and controls the volume expansion of lithium anodes. Moreover, compared with the commonly used carbonate electrolytes, the battery containing BSA has the best overall performance. Methodologically, the results can be extended to other additives containing Si-O functional groups to replace the same type of fluorine-containing additives.
ABSTRACT
Deep eutectic solvents (DESs) were synthesized using menthol as hydrogen bond acceptor (HBA) and different carbon chain carboxylic acids as hydrogen bond donors (HBD). The liquid equilibrium (LLE) experiment was used to determine the distribution coefficient (ß) and slectivity (S) at standard atmospheric pressure and temperature. The effect of DESs on the separation efficiency was discussed by changing the proportion. Non-random two fluid (NRTL) model was used to correlate the experimental data. The molecular dynamics (MD) simulation method was used to investigate the micro mechanism of the extraction process. The results show van der Waals force plays a leading role in the interaction between solvents and tert-butyl alcohol (TBA) and week force with water. Compared with experimental and simulation results, the interaction between DESs and TBA would also be affected by the change of the number of HBD carbon chains, and DESs with decanoic acid as HBD has the best separation effect, which verifies the feasibility of separating high alcohol compounds from water by DESs and then treating them by DESs.
Subject(s)
Menthol , tert-Butyl Alcohol , Deep Eutectic Solvents , Solvents/chemistry , Water/chemistryABSTRACT
The striatum is primarily composed of two types of medium spiny neurons (MSNs) expressing either D1- or D2-type dopamine receptors. However, the fate determination of these two types of neurons is not fully understood. Here, we found that D1 MSNs undergo fate switching to D2 MSNs in the absence of Zfp503. Furthermore, scRNA-seq revealed that the transcription factor Zfp503 affects the differentiation of these progenitor cells in the lateral ganglionic eminence (LGE). More importantly, we found that the transcription factors Sp8/9, which are required for the differentiation of D2 MSNs, are repressed by Zfp503. Finally, sustained Zfp503 expression in LGE progenitor cells promoted the D1 MSN identity and repressed the D2 MSN identity. Overall, our findings indicated that Zfp503 promotes the D1 MSN identity and represses the D2 MSN identity by regulating Sp8/9 expression during striatal MSN development.
ABSTRACT
The striatum is the main input structure of the basal ganglia, receiving information from the cortex and the thalamus and consisting of D1- and D2- medium spiny neurons (MSNs). D1-MSNs and D2-MSNs are essential for motor control and cognitive behaviors and have implications in Parkinson's Disease. In the present study, we demonstrated that Sp9-positive progenitors produced both D1-MSNs and D2-MSNs and that Sp9 expression was rapidly downregulated in postmitotic D1-MSNs. Furthermore, we found that sustained Sp9 expression in lateral ganglionic eminence (LGE) progenitor cells and their descendants led to promoting D2-MSN identity and repressing D1-MSN identity during striatal development. As a result, sustained Sp9 expression resulted in an imbalance between D1-MSNs and D2-MSNs in the mouse striatum. In addition, the fate-changed D2-like MSNs survived normally in adulthood. Taken together, our findings supported that Sp9 was sufficient to promote D2-MSN identity and repress D1-MSN identity, and Sp9 was a negative regulator of D1-MSN fate.
ABSTRACT
Working memory (WM) plays an important role in cognitive activity. The WM system is used to temporarily store information in learning and decision-making. WM always functions in many aspects of daily life, such as the short-term memory of words, cell phone verification codes, and cell phone numbers. In young adults, studies have shown that a central memory store is limited to three to five meaningful items. Little is known about how WM functions at the microscopic neural level, but appropriate neural network computational models can help us gain a better understanding of it. In this study, we attempt to design a microscopic neural network model to explain the internal mechanism of WM. The performance of existing positive feedback models depends on the parameters of a synapse. We use a negative-derivative feedback mechanism to counteract the drift in persistent activity, making the hybrid positive and negative-derivative feedback (HPNF) model more robust to common disturbances. To fulfill the mechanism of WM at the neural circuit level, we construct two main neural networks based on the HPNF model: a memory-storage sub-network (the memory-storage sub-network is composed of several sets of neurons, so we call it "SET network", or "SET" for short) with positive feedback and negative-derivative feedback and a storage distribution network (SDN) designed by combining SET for memory item storage and memory updating. The SET network is a neural information self-sustaining mechanism, which is robust to common disturbances; the SDN constructs a storage distribution network at the neural circuit level; the experimental results show that our network can fulfill the storage, association, updating, and forgetting of information at the level of neural circuits, and it can work in different individuals with little change in parameters.
ABSTRACT
The striatum is a central regulator of behavior and motor function through the actions of D1 and D2 medium-sized spiny neurons (MSNs), which arise from a common lateral ganglionic eminence (LGE) progenitor. The molecular mechanisms of cell fate specification of these two neuronal subtypes are incompletely understood. Here, we found that deletion of murine Meis2, which is highly expressed in the LGE and derivatives, led to a large reduction in striatal MSNs due to a block in their differentiation. Meis2 directly binds to the Zfp503 and Six3 promoters and is required for their expression and specification of D1 and D2 MSNs, respectively. Finally, Meis2 expression is regulated by Dlx1/2 at least partially through the enhancer hs599 in the LGE subventricular zone. Overall, our findings define a pathway in the LGE whereby Dlx1/2 drives expression of Meis2, which subsequently promotes the fate determination of striatal D1 and D2 MSNs via Zfp503 and Six3.
Subject(s)
Corpus Striatum/metabolism , Homeodomain Proteins/metabolism , Neurons/metabolism , Transcription Factors/metabolism , Animals , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Eye Proteins/genetics , Eye Proteins/metabolism , Homeodomain Proteins/genetics , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Lateral Ventricles/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neural Stem Cells/cytology , Neural Stem Cells/metabolism , Neurogenesis , Neurons/cytology , Olfactory Bulb/growth & development , Olfactory Bulb/metabolism , Promoter Regions, Genetic , Protein Binding , Transcription Factors/genetics , Tubulin/genetics , Tubulin/metabolism , Homeobox Protein SIX3ABSTRACT
Specification of the progenitors' regional identity is a pivotal step during development of the cerebral cortex and basal ganglia. The molecular mechanisms underlying progenitor regionalization, however, are poorly understood. Here we showed that the transcription factor Vax1 was highly expressed in the developing subpallium. In its absence, the RNA-Seq analysis, in situ RNA hybridization, and immunofluorescence staining results showed that the cell proliferation was increased in the subpallium, but the neuronal differentiation was blocked. Moreover, the dLGE expands ventrally, and the vLGE, MGE, and septum get smaller. Finally, overexpressed VAX1 in the LGE progenitors strongly inhibits Gsx2 expression. Taken together, our findings show that Vax1 is crucial for subpallium regionalization by repressing Gsx2.
Subject(s)
Corpus Striatum/embryology , Corpus Striatum/metabolism , Globus Pallidus/embryology , Globus Pallidus/metabolism , Homeodomain Proteins/biosynthesis , Neuropeptides/biosynthesis , Animals , Corpus Striatum/cytology , Globus Pallidus/cytology , Homeodomain Proteins/antagonists & inhibitors , Homeodomain Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neural Stem Cells/metabolism , Neurogenesis/physiology , Neuropeptides/geneticsABSTRACT
The striatum is structurally highly diverse, and its organ functionality critically depends on normal embryonic development. Although several studies have been conducted on the gene functional changes that occur during striatal development, a system-wide analysis of the underlying molecular changes is lacking. Here, we present a comprehensive transcriptome profile that allows us to explore the trajectory of striatal development and identify the correlation between the striatal development and Huntington's disease (HD). Furthermore, we applied an integrative transcriptomic profiling approach based on machine learning to systematically map a global landscape of 277 transcription factor (TF) networks. Most of these TF networks are linked to biological processes, and some unannotated genes provide information about the corresponding mechanisms. For example, we found that the Meis2 and Six3 were crucial for the survival of striatal neurons, which were verified using conditional knockout (CKO) mice. Finally, we used RNA-Seq to speculate their downstream targets.
Subject(s)
Apoptosis , Corpus Striatum/pathology , Gene Expression Profiling , Gene Regulatory Networks , Huntington Disease/genetics , Huntington Disease/pathology , Transcription Factors/genetics , Transcriptome , Animals , Case-Control Studies , Databases, Genetic , Eye Proteins/genetics , Gene Expression Regulation, Developmental , Genetic Predisposition to Disease , Homeodomain Proteins/genetics , Humans , Machine Learning , Mice, Knockout , Nerve Tissue Proteins/genetics , Phenotype , RNA-Seq , Homeobox Protein SIX3ABSTRACT
Mouse cortical radial glial cells (RGCs) are primary neural stem cells that give rise to cortical oligodendrocytes, astrocytes, and olfactory bulb (OB) GABAergic interneurons in late embryogenesis. There are fundamental gaps in understanding how these diverse cell subtypes are generated. Here, by combining single-cell RNA-Seq with intersectional lineage analyses, we show that beginning at around E16.5, neocortical RGCs start to generate ASCL1+EGFR+ apical multipotent intermediate progenitors (MIPCs), which then differentiate into basal MIPCs that express ASCL1, EGFR, OLIG2, and MKI67. These basal MIPCs undergo several rounds of divisions to generate most of the cortical oligodendrocytes and astrocytes and a subpopulation of OB interneurons. Finally, single-cell ATAC-Seq supported our model for the genetic logic underlying the specification and differentiation of cortical glial cells and OB interneurons. Taken together, this work reveals the process of cortical radial glial cell lineage progression and the developmental origins of cortical astrocytes and oligodendrocytes.
Subject(s)
Neural Stem Cells , Neurogenesis , Animals , Cell Differentiation , Mice , Neuroglia , OligodendrogliaABSTRACT
OBJECTIVE: To assess the performance of high-performance liquid chromatography (HPLC) combined with capillary monolithic column molecularly imprinted with metal organic frame (UiO-66-NH2@MIPs capillary monolithic column) for enrichment, purification and detection of Ponceau 4R in Carthami flos. METHODS: UiO-66-NH2@MIPs monolithic columns were prepared via in situ polymerization, and the adsorption properties and morphology of the columns were characterized by HPLC, scanning electron microscopy (SEM) and infrared (IR) spectral analysis. HPLC with the prepared columns was performed for detecting the content of Ponceau 4R in Carthami flos samples. RESULTS: The UiO-66-NH2@MIPs system showed a good linearity for detecting Ponceau 4R over the concentration range of 0.1-10.0 µg/mL with a correlation coefficient > 0.9999 and a detection limit (S/N=3) of 2.7×10-4 µg/mL. The mean recovery of Ponceau 4R in Carthami flos samples ranged from 82.60% to 105.56%, and the intra-day and inter-day relative standard deviation (RSD) values ranged from 2.4% to 3.4%. The recycling experiment showed that the system could be reused for sensitive detection of Ponceau 4R in Carthami flos. The capacity of UiO-66-NH2@MIPs column was 0.178 µg/mg, which was superior to that of other monolithic columns (0.089, 0.080, and 0.111 µg/ mg), demonstrating that the addition of UiO-66-NH2 increased the adsorption capacity of the system. Under the optimized conditions, the UiO-66-NH2@MIPs-HPLC system had an enrichment factor of over 73 folds with obviously reduced interference by the impurity peaks. CONCLUSIONS: The UiO-66-NH2@MIPs column-HPLC system has much better performance for enrichment, purification and detection of Ponceau 4R in Carthami flos than direct HPLC.
Subject(s)
Chromatography, High Pressure Liquid , Azo Compounds , Metals , Molecular Imprinting , Naphthalenesulfonates , Solid Phase ExtractionABSTRACT
Fish mucus acts as a physiological and immunological barrier for maintaining normal fish physiology and conferring defense against pathogens infection. Here we report proteomic profiling of skin mucus of yellow catfish before and after E. ictaluri infection by Label-free LC-MS/MS approach. A total of 918 non-redundant proteins were identified from 54443 spectra referring to yellow catfish genome database. Further annotation via GO and KEGG database revealed complex protein composition of yellow catfish mucus. Besides structural proteins in mucus, a lot of immune-related proteins were retrieved, such as lectins, complement components, antibacterial peptides and immunoglobins. 133 differentially-expressed proteins (DEPs), including 76 up-regulated and 57 down-regulated proteins, were identified, most of which were enriched into 17 pathways centering on "immune system" category with 33 proteins involved. Consistently, significant proliferation of mucus-secreting goblet cells and CYPA-expressing cells were observed along outside of yellow catfish skin after E. ictaluri infection, indicating an enhanced immune response to E. ictaluri infection in yellow catfish skin mucus. The proteomic data provide systematic protein information to comprehensively understand the biological function of yellow catfish skin mucus in response to bacterial infection.
Subject(s)
Catfishes/genetics , Enterobacteriaceae Infections/veterinary , Fish Proteins/genetics , Mucus/immunology , Skin/immunology , Animals , Catfishes/immunology , Chromatography, Liquid , Edwardsiella ictaluri , Enterobacteriaceae Infections/immunology , Fish Diseases/immunology , Gene Expression Profiling , Male , Mucus/microbiology , Proteome , Skin/microbiology , Tandem Mass SpectrometryABSTRACT
The striatum, the major component of the basal ganglia, consists of the caudate-putamen, nucleus accumbens and olfactory tubercle. The striatal principal projection neurons are comprised of medium spiny neurons (MSNs) with two dopamine receptors: DRD1 (D1 MSNs) and DRD2 (D2 MSNs). In the present study, we demonstrate that Zfhx3 is strongly expressed in the boundary of the subventricular zone (SVZ)/mantle zone (MZ) of the lateral ganglionic eminence (LGE), and its expression in the striatum is downregulated during the first postnatal week. At the cellular level, Zfhx3 is selectively expressed in immature D1 MSNs. In Zfhx3 conditional knockouts, we observed an accumulation of progenitors in the LGE SVZ at E16.5 and P0, and an increase in apoptosis in the postnatal striatum. BrdU birthdating experiments revealed that late born D1 MSN production was compromised. Accordingly, we observed a significant reduction in the number of D1 MSNs, whereas the number of D2 MSNs remained unaffected in the striatum of Zfhx3 conditional knockouts at P11. We concluded that Zfhx3 plays a critical role in the differentiation and survival of late born D1 MSNs.
Subject(s)
Cell Differentiation/physiology , Corpus Striatum/cytology , Homeodomain Proteins/metabolism , Neurons/cytology , Animals , Mice , Mice, Knockout , Neural Stem Cells/metabolism , Neurons/metabolism , Receptors, Dopamine D1/metabolismABSTRACT
Cortical interneurons are derived from the subcortical medial ganglionic eminence (MGE), caudal ganglionic eminence (CGE) and preoptic area (POA). CGE-derived cortical interneurons, which comprise around 30% of all cortical interneurons, mainly express Htr3a, calretinin (CR), Reelin (RELN) and vasoactive intestinal polypeptide (VIP). In the present study, we show that transcription factors Sp8 and Sp9 are co-expressed in the subventricular zone (SVZ) of the dorsal CGE. Conditional knockout of Sp8/9 using the Gsx2-Cre transgenic line results in severe loss of CGE-derived cortical interneurons. We observed migration defects of Sp8/9 double mutant CGE-derived cortical interneurons as they had longer leading processes than controls and they ectopically accumulated in the CGE. Dlx5/6-CIE conditional deletion of Sp8/9 also leads to a significant reduction in the CGE-derived cortical interneurons. We provide evidence that Sp8/9 coordinately regulate CGE-derived cortical interneuron development in part through repressing the expression of Pak3, Robo1, and Slit1. Finally, we show that Cxcl14, a member of the CXC chemokine family, is mainly expressed in CGE-derived interneurons in cortical layers I and II, and its expression is critically dependent on SP8.
Subject(s)
Brain/growth & development , Brain/metabolism , Cell Movement/physiology , DNA-Binding Proteins/metabolism , Interneurons/metabolism , Transcription Factors/metabolism , Animals , Chemokines, CXC/metabolism , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Transgenic , Neurogenesis/physiology , Reelin Protein , Stem Cell Niche/physiologyABSTRACT
Neural stem cells in the subventricular zone (SVZ) of the lateral ventricle generate new interneurons, which migrate tangentially through the rostral migratory stream (RMS) to the olfactory bulb (OB). The PROK2 (prokineticin 2) and PROKR2 (prokineticin receptor 2) signaling pathway has been identified to cause human Kallmann syndrome, a developmental disease that associates hypogonadism with anosmia (OB developmental defects). However, the identities and properties of PROK2+ and PROKR2+ cells in the SVZ-RMS-OB remain largely unknown. Here we examine the expression patterns of Prok2 and Prokr2 in the SVZ-RMS-OB using Prok2EGFP transgenic and Prokr2LacZ/+ knockin mice. Our results show that Prokr2 is expressed in postmitotic immature interneurons in the SVZ-RMS-OB. Prok2 is not expressed in the SVZ, but a few PROK2+ cells are found in the medial part of the RMS; they are not neural progenitors or migrating neuroblasts. In the OB, Prok2 is expressed in a subset of granule cells and tufted cells, but no coexpression of Prok2 and Prokr2 in the OB cells is observed. In Prok2 and Prokr2 mutant mice, severe tangential and radial migration defects of neuroblasts in the SVZ-RMS-OB result in loss of ~75% of GABAergic interneurons in the OB. These analyses demonstrate that PROK2/PROKR2 signaling is crucial for the tangential and radial migration of OB interneurons.