Expediting Next-Generation Hybrid Technology in Recalcitrant Maize Inbreds through In Vivo Targeted Activity of CRISPR/Cas9.

The Manipulated Genic Male Sterile Maintainer (MGM) system, a next-generation hybrid seed technology, enables efficient production of sortable seeds from genic male sterile (GMS) lines. However, implementing robust MGM systems in commercial maize inbred lines requires stable transformation, a genotype-specific and laborious process. This study aimed to integrate MGM technology into the commercial maize inbred line Z372, developing both GMS and MGM lines. We utilized the MGM line ZC01-3A-7, which contains the MS26ΔE5 editor T-DNA and MGM T-DNA, previously established in the highly transformable ZC01 recipient plants. Through a combination of crossing and backcrossing with Z372, we targeted the fertility gene Ms26 within the Z372 genome for mutation using the in vivo CRISPR/Cas9 activity within the MS26ΔE5 editor T-DNA construct. This approach facilitated precise editing of the Ms26 locus, minimizing linkage drag associated with the Ms26 mutation. Whole-genome SNP analysis achieved a 98.74% recovery rate for GMS and 96.32% for MGM in the BC2F2 generation. Importantly, the Z372-GMS line with the ms26ΔE5 mutation is non-transgenic, avoiding linkage drag and demonstrating production readiness. This study represents a significant advancement in maize breeding, enabling the rapid generation of GMS and MGM lines for efficient hybrid seed production.

Gonadal Transcriptome Sequencing Analysis Reveals the Candidate Sex-Related Genes and Signaling Pathways in the East Asian Common Octopus, Octopus sinensis.

The East Asian common octopus (Octopus sinensis) is an economically important species among cephalopods. This species exhibits a strict dioecious and allogamous reproductive strategy, along with a phenotypic sexual dimorphism, where the third right arm differentiates into hectocotylus in males. However, our understanding of the molecular mechanisms that underlie sex determination and differentiation in this species remains limited. In the present study, we surveyed gene-expression profiles in the immature male and female gonads of O. sinensis based on the RNA-seq, and a total of 47.83 Gb of high-quality data were generated. Compared with the testis, we identified 8302 differentially expressed genes (DEGs) in the ovary, of which 4459 genes were up-regulated and 3843 genes were down-regulated. Based on the GO enrichment, many GO terms related to sex differentiation were identified, such as sex differentiation (GO: 0007548), sexual reproduction (GO: 0019953) and male sex differentiation (GO: 0046661). A KEGG classification analysis identified three conserved signaling pathways that related to sex differentiation, including the Wnt signaling pathway, TGF-ß signaling pathway and Notch signaling pathway. Additionally, 21 sex-related DEGs were selected, of which 13 DEGs were male-biased, including Dmrt1, Foxn5, Foxj1, Sox30, etc., and 8 DEGs were female-biased, including Sox14, Nanos3, ß-tubulin, Suh, etc. Ten DEGs were used to verify the expression patterns in the testis and ovary using the RT-qPCR method, and the results showed that the expression level shown by RT-qPCR was consistent with that from the RNA-seq, which confirmed the reliability of the transcriptome data. The results presented in this study will not only contribute to our understanding of sex-formation mechanisms in O. sinensis but also provide the foundational information for further investigating the molecular mechanisms that underline its gonadal development and facilitate the sustainable development of octopus artificial breeding.

Effect of Grain Size on Nanometric Cutting of Polycrystalline Silicon via Molecular Dynamics Simulation.

The grain size effect is an important factor in determining the material removal behavior of polycrystalline silicon (p-Si). In the present study, to improve the understanding of nanoscale machining of p-Si, we performed molecular dynamics simulation of nanometric cutting on a p-Si workpiece and discussed the grain size effect on material removal behavior and subsurface damage formation. The simulation results indicate that when cutting on the polycrystal workpiece, the material removal process becomes unstable compared with single crystals. Higher removal efficiency, less elastic recovery and higher frictional coefficient are observed as the average grain size decreases. In the subsurface workpiece, when the grain size decreases, slip along grain boundaries merges as a nonnegligible process of the plastic deformation and suppresses the elastic deformation ahead of the cutting tool. It is also revealed that when cutting on a polycrystal workpiece with smaller grains, the average stress decreases while the workpiece temperature increases due to the impediment of heat transfer by grain boundaries. These results could provide a fundamental understanding in the material deformation mechanism of p-Si during nanoscale machining.

Small extracellular vesicle CA1 as a promising diagnostic biomarker for nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC), a malignant cancer originating from the epithelial cells of the nasopharynx, presents diagnostic challenges with current methods such as plasma Epstein-Barr virus (EBV) DNA testing showing limited efficacy. This study focused on identifying small extracellular vesicle (sEV) proteins as potential noninvasive biomarkers to enhance NPC diagnostic accuracy. We isolated sEVs from plasma and utilized 4D label-free proteomics to identify differentially expressed proteins (DEPs) among healthy controls (NC = 10), early-stage NPC (E-NPC = 10), and late-stage NPC (L-NPC = 10). Eighteen sEV proteins were identified as potential biomarkers. Subsequently, parallel reaction monitoring (PRM) proteomic analysis preliminarily confirmed sEV carbonic anhydrase 1 (CA1) as a highly promising biomarker for NPC, particularly in early-stage diagnosis (NC = 15; E-NPC = 10; L-NPC = 15). To facilitate this, we developed an automated, high-throughput and highly sensitive CA1 immune-chemiluminescence chip technology characterized by a broad linear detection range and robust controls. Further validation in an independent retrospective cohort (NC = 89; E-NPC = 39; L-NPC = 172) using this technology confirmed sEV CA1 as a reliable diagnostic biomarker for NPC (AUC = 0.9809) and E-NPC (AUC = 0.9893), independent of EBV-DNA testing. Notably, sEV CA1 exhibited superior diagnostic performance compared to EBV-DNA, with a significant incremental net reclassification improvement of 27.61 % for NPC and 72.11 % for E-NPC detection. Thus, this study identifies sEV CA1 as an innovative diagnostic biomarker for NPC and E-NPC independent of EBV-DNA. Additionally, it establishes an immune-chemiluminescence chip technology for the detection of sEV CA1 protein, paving the way for further validation and clinical application.

Adaptively identify and refine ill-posed regions for accurate stereo matching.

Stereo matching cost constrains the consistency between pixel pairs. However, the consistency constraint becomes unreliable in ill-posed regions such as occluded or ambiguous regions of the images, making it difficult to explore hidden correspondences. To address this challenge, we introduce an Error-area Feature Refinement Mechanism (EFR) that supplies context features for ill-posed regions. In EFR, we innovatively obtain the suspected error region according to aggregation perturbations, then a simple Transformer module is designed to synthesize global context and correspondence relation with the identified error mask. To better overcome existing texture overfitting, we put forward a Dual-constraint Cost Volume (DCV) that integrates supplementary constraints. This effectively improves the robustness and diversity of disparity clues, resulting in enhanced details and structural accuracy. Finally, we propose a highly accurate stereo matching network called Error-rectify Feature Guided Stereo Matching Network (ERCNet), which is based on DCV and EFR. We evaluate our model on several benchmark datasets, achieving state-of-the-art performance and demonstrating excellent generalization across datasets. The code is available at https://github.com/dean7liu/ERCNet_2023.

Interferon-induced transmembrane protein-1 competitively blocks Ephrin receptor A2-mediated Epstein-Barr virus entry into epithelial cells.

Epstein-Barr virus (EBV) can infect both B cells and epithelial cells (ECs), causing diseases such as mononucleosis and cancer. It enters ECs via Ephrin receptor A2 (EphA2). The function of interferon-induced transmembrane protein-1 (IFITM1) in EBV infection of ECs remains elusive. Here we report that IFITM1 inhibits EphA2-mediated EBV entry into ECs. RNA-sequencing and clinical sample analysis show reduced IFITM1 in EBV-positive ECs and a negative correlation between IFITM1 level and EBV copy number. IFITM1 depletion increases EBV infection and vice versa. Exogenous soluble IFITM1 effectively prevents EBV infection in vitro and in vivo. Furthermore, three-dimensional structure prediction and site-directed mutagenesis demonstrate that IFITM1 interacts with EphA2 via its two specific residues, competitively blocking EphA2 binding to EBV glycoproteins. Finally, YTHDF3, an m6A reader, suppresses IFITM1 via degradation-related DEAD-box protein 5 (DDX5). Thus, this study underscores IFITM1's crucial role in blocking EphA2-mediated EBV entry into ECs, indicating its potential in preventing EBV infection.

Safety and efficacy of a low-dose combination of midazolam, alfentanil, and propofol for deep sedation of elderly patients undergoing ERCP.

BACKGROUND: Proper sedation of patients, particularly elderly individuals, who are more susceptible to sedation-related complications, is of significant importance in endoscopic retrograde cholangiopancreatography (ERCP). This study aims to assess the safety and efficacy of a low-dose combination of midazolam, alfentanil, and propofol for deep sedation in elderly patients undergoing ERCP, compared to a group of middle-aged patients. METHODS: The medical records of 610 patients with common bile duct stones who underwent elective ERCP under deep sedation with a three-drug regimen, including midazolam, alfentanil, and propofol at Shandong Provincial Third Hospital from January 2023 to September 2023 were retrospectively reviewed in this study. Patients were categorized into three groups: middle-aged (50-64 years, n = 202), elderly (65-79 years, n = 216), and very elderly (≥ 80 years, n = 192). Intraoperative vital signs and complications were compared among these groups. RESULTS: The three groups showed no significant difference in terms of intraoperative variation of systolic blood pressure (P = 0.291), diastolic blood pressure (P = 0.737), heart rate (P = 0.107), peripheral oxygen saturation (P = 0.188), bispectral index (P = 0.158), and the occurrence of sedation-related adverse events including hypotension (P = 0.170) and hypoxemia (P = 0.423). CONCLUSION: The results suggest that a low-dose three-drug regimen consisting of midazolam, alfentanil, and propofol seems safe and effective for deep sedation of elderly and very elderly patients undergoing ERCP procedures. However, further studies are required to verify these findings and clarify the benefits and risks of this method.

The maize PLASTID TERMINAL OXIDASE (PTOX) locus controls the carotenoid content of kernels.

Carotenoids perform a broad range of important functions in humans; therefore, carotenoid biofortification of maize (Zea mays L.), one of the most highly produced cereal crops worldwide, would have a global impact on human health. PLASTID TERMINAL OXIDASE (PTOX) genes play an important role in carotenoid metabolism; however, the possible function of PTOX in carotenoid biosynthesis in maize has not yet been explored. In this study, we characterized the maize PTOX locus by forward- and reverse-genetic analyses. While most higher plant species possess a single copy of the PTOX gene, maize carries two tandemly duplicated copies. Characterization of mutants revealed that disruption of either copy resulted in a carotenoid-deficient phenotype. We identified mutations in the PTOX genes as being causal of the classic maize mutant, albescent1. Remarkably, overexpression of ZmPTOX1 significantly improved the content of carotenoids, especially ß-carotene (provitamin A), which was increased by ~threefold, in maize kernels. Overall, our study shows that maize PTOX locus plays an important role in carotenoid biosynthesis in maize kernels and suggests that fine-tuning the expression of this gene could improve the nutritional value of cereal grains.

Photochemically Controlled Release of the Glucose Transporter 1 Inhibitor for Glucose Deprivation Responses and Cancer Suppression Research.

Cancer cells need a greater supply of glucose mainly due to their aerobic glycolysis, known as the Warburg effect. Glucose transport by glucose transporter 1 (GLUT1) is the rate-limiting step for glucose uptake, making it a potential cancer therapeutic target. However, GLUT1 is widely expressed and performs crucial functions in a variety of cells, and its indiscriminate inhibition will cause serious side effects. In this study, we designed and synthesized a photocaged GLUT1 inhibitor WZB117-PPG to suppress the growth of cancer cells in a spatiotemporally controllable manner. WZB117-PPG exhibited remarkable photolysis efficiency and substantial cytotoxicity toward cancer cells under visible light illumination with minimal side effects, ensuring its safety as a potential cancer therapy. Furthermore, our quantitative proteomics data delineated a comprehensive portrait of responses in cancer cells under glucose deprivation, underlining the mechanism of cell death via necrosis rather than apoptosis. We reason that our study provides a potentially reliable cancer treatment strategy and can be used as a spatiotemporally controllable trigger for studying nutrient deprivation-related stress responses.

Revealing the Mutually Enhanced Mechanism of Necroptosis and Immunotherapy Induced by Defect Engineering and Piezoelectric Effect.

Owing to low immunogenicity-induced immune escape and short-term circulating immune responses, the efficiency of immunotherapy is unsatisfactory. Therefore, triggering immunogenic cell death and establishing a long-term, mutually reinforced treatment modality are urgent challenges. In this study, ultrathin CaBi2 Nb2 O9 nanosheets with tunable oxygen vacancies (abbreviated as CBNO-OV1) are prepared for synergistic necroptosis and immunotherapy. The optimized vacancy concentration significantly improves the piezoelectric effect under ultrasound irradiation, thereby considerably improving the generation of reactive oxygen species (ROS). Density functional theory shows that oxygen vacancies can improve the efficiency of electron hole separation by suppressing their recombination, thus resulting in enhanced piezocatalytic activity. Moreover, the piezoelectric effect improves the permeability of tumor cell membranes, thus resulting in Ca2+ influx. Additionally, CBNO-OV1 also releases a portion of Ca2+ , which induces necroptosis assisted by explosive ROS. Ribonucleic acid transcription tests suggest the mechanisms associated with immune response activation and necroptosis. More importantly, necroptosis can trigger a significant immune response in vivo, thus activating macrophage M1 polarization through the NF-kappa B pathway and promoting T-cell differentiation.Tumor Necrosis Factor-α differentiated from macrophages conversely promotes necroptosis, thus realizing a mutually enhanced effect. This study demonstrates the feasibility of mutually reinforced necroptosis and immunotherapy for amplifying tumor efficacy.

A bubble-enhanced lanthanide-doped up/down-conversion platform with tumor microenvironment response for dual-modal photoacoustic and near-infrared-II fluorescence imaging.

As an important tumor diagnosis strategy in precision medicine, multimodal imaging has been widely studied. However, the weak imaging signal with low spatial resolution and the constant signal of lack of specific activation severely limit its disease diagnosis. Herein, a bubble-enhanced lanthanide-based up/down-conversion platform with tumor microenvironment response for dual-mode imaging, LDNP@DMSN-Au@CaCO3 nanoparticles (named as LDAC NPs) were successfully developed. Combining the advantages of photoacoustic imaging (PAI) and the second near-infrared window (NIR-II) fluorescence imaging (FI), significantly improved the accuracy of diseases diagnosis. LDAC NPs with flower-like structure were synthesized through the encapsulation of uniform lanthanide-doped nanoparticles (NaYbF4:Ce,Er@NaYF4 named LDNPs) with dendritic mesoporous silica (DMSN). The gold nanoparticles (Au NPs) were then in situ grown on the surface of DMSN and the surface were finally coated with a layer of calcium carbonate (CaCO3). Under the excitation of the 980 nm laser, LDNPs showed strong emission of NIR-II at 1550 nm due to the doping of Ce and Er ions, showcasing excellent spatial resolution and deep tissue penetration characteristics, while the resulting visible light emission (540 nm) enables Au NPs to generate PAI signals with the aid of LDNPs via the fluorescence resonance energy transfer effect. In acidic tumoral environment, CaCO3 layer could produce CO2 microbubbles, and the PAI signals of LDAC NPs could be further enhanced with the generation of CO2 bubbles due to the bubble cavitation effect. Simultaneously, the NIR-II FI of LDAC NPs was self-enhanced with the degradation of the CaCO3. This intelligent nanoparticle with stimulus-activated dual-mode imaging capability holds great promise in future precision diagnostics.

Organic Species-Intercalated Vanadium Oxide for Sodium-Ion Battery: Mixed-Anion Coordination Effect, Enhanced d-p Orbital Hybridization, and Topotactic Phase Conversion Induced by N-Substitution.

Sodium-ion battery (SIB) is a reasonable alternative to lithium-ion battery (LIB) in the field of grid-scale energy storage systems. Unfortunately, the development of appropriate cathode material is a bottleneck in the field of SIB. In the present work, (p-TQ)-VO, formulated as (p-TQ)0.2V2O5·0.38H2O, was synthesized based on a facile hydrothermal reaction of V2O5 and methylhydroquinone (p-HTQ). And when V2O5 was replaced by VN, (p-TQ)-VN, formulated as (p-TQ)0.22V2(O/N)5, was prepared instead. The (p-TQ)-VO sample displays good electrochemical performance as the SIB cathode. And (p-TQ)-VN shows a much higher capacity at a small current density, and it can maintain structural integrity with partial topotactic phase transformation into NaxV2O5 during the discharge/charge process. A series of characterizations of (p-TQ)-VO and (p-TQ)-VN reveals the successful intercalation of p-TQ into the layered V2O5 with a (001) lattice spacing of 13.7 and 10.7 Å, respectively. In (p-TQ)-VN, partial terminal oxygen (Ot) atoms from the V-O-V layer have been substituted by N atoms, which can boost the orbital hybridization of V 3d and Ot 2p, shorten the V-Ot bonds in the c-axial direction, and elongate the V-O bonds in the ab plane with compressed {VO4N2} octahedra, giving rise to mixed-anion coordination effect. As a result, the enhanced electron densities around the Ot atoms of the V-O-V layer can facilitate the affinity toward the inserted Na+ ions, leading to partial phase conversion into NaNO2/NaNO3. Moreover, density functional density (DFT) calculations reveal that the N-incorporation can improve electron conductivity with richer molecular orbital energy levels, resulting in multistep redox reactions and enhanced capacity.

Numerical Investigation on the Effects of Grain Size and Grinding Depth on Nano-Grinding of Cadmium Telluride Using Molecular Dynamics Simulation.

Cadmium telluride (CdTe) is known as an important semiconductor material with favorable physical properties. However, as a soft-brittle material, the fabrication of high-quality surfaces on CdTe is quite challenging. To improve the fundamental understanding of the nanoscale deformation mechanisms of CdTe, in this paper, MD simulation was performed to explore the nano-grinding process of CdTe with consideration of the effects of grain size and grinding depth. The simulation results indicate that during nano-grinding, the dominant grinding mechanism could switch from elastic deformation to ploughing, and then cutting as the grinding depth increases. It was observed that the critical relative grain sharpness (RGS) for the transition from ploughing to cutting is greatly influenced by the grain size. Furthermore, as the grinding depth increases, the dominant subsurface damage mechanism could switch from surface friction into slip motion along the <110> directions. Meanwhile, as the grain size increases, less friction-induced damage is generated in the subsurface workpiece, and more dislocations are formed near the machined groove. Moreover, regardless of the grain size, it was observed that the generation of dislocation is more apparent as the dominant grinding mechanism becomes ploughing and cutting.

Acute Social Stress Influences Moral Decision-Making Under Different Social Distances in Young Healthy Men.

Acute social stress has been shown to influence social decision-making. This study aimed to examine how social distance modulates the influence of acute social stress on young male moral decision-making. Sixty healthy male college students were randomly divided to be exposed to the Trier Social Stress Test (TSST) or a placebo version of the TSST (P-TSST) before they performed moral decision-making tasks. The results showed that participants under acute social stress showed obvious increases in subjective stress perception, negative affect, salivary cortisol, and alpha-amylase and made more altruistic choices for others compared to the control group. However, social distance regulates the promotion of this acute social stress, with the promotion effect being stronger in socially distant others. Furthermore, the interpersonal order difference of different social distances in altruistic decisions is smaller in low-conflict dilemmas than in high-conflict dilemmas. In addition, an increase in salivary cortisol was positively correlated with altruistic choices toward both acquaintances and strangers, whereas an increase in salivary alpha-amylase was only positively correlated with altruistic choices toward friends. The results suggest that social distance modulates the promotion of acute social stress on moral decision-making, which might stem from the divergent effects of cortisol and alpha-amylase.

Corrigendum: A minimally manipulated preservation and virus inactivation method for amnion/chorion.

[This corrects the article DOI: 10.3389/fbioe.2022.952498.].

Pollen self-elimination CRISPR-Cas genome editing prevents transgenic pollen dispersal in maize.

This study reports the development of a programmed pollen self-elimination CRISPR-Cas (PSEC) system in which the pollen is infertile when PSEC is present in haploid pollen. PSEC can be inherited through the female gametophyte and retains genome editing activity in vivo across generations. This system could greatly alleviate serious concerns about the widespread diffusion of genetically modified (GM) elements into natural and agricultural environments via outcrossing.

Application of a biodegradable poly(butylene adipate-co-terephthalate) membrane for phenol pervaporation recovery.

In the field of membrane separation, the environmental concerns caused by spent membranes are becoming increasingly serious, which contradicts the concept of sustainable development. Based on this, a biodegradable poly(butylene adipate-co-terephthalate) (PBAT) membrane was used for the first time in the pervaporation separation of phenol, a high boiling point organic compound (HBOC). By using the PBAT membrane, outstanding separation efficiency was achieved, and environmental pollution and disposal issues were also avoided. The separation process and mechanism of the PBAT membrane were systematically studied through the experiment together with molecular dynamics (MD) simulation. The swelling experiment and intermolecular interaction energy calculation demonstrated that the PBAT membrane had a strong affinity for phenol. Further simulation concluded that higher phenol concentration increased the number of hydrogen bonds so that the membrane was more greatly swollen. Meanwhile, the simulations on the adsorption, diffusion and permeation predicted that the PBAT membrane had excellent separation performance for phenol. Besides MD simulation, the influences of feed concentration and temperature on pervaporation performance were also investigated by experiment. The results showed that the flux of each component increased with the feed concentration. This phenomenon was attributed to the preferential adsorption of phenol by the PBAT membrane, which resulted in large free volumes and cavities within the membrane, accelerating the diffusion of molecules. In addition, it was found that the optimal operating temperature was 333 K with the best separation performance. This study confirms that the biodegradable PBAT membrane is valuable for the recovery of high boiling point organic compounds (HBOCs) such as phenol.

An approach for linear optical phase demodulation using a single photodetector.

In this paper, we propose and experimentally verify a phase-modulated radio-over-fiber (RoF) link capable of transmitting the radio frequency (RF) signal linearly. By executing the Kramers-Kronig (KK) algorithm at the receiver, the proposed link can accomplish linear optical phase demodulation with a single photodetector rather than a coherent receiver. In the 16-quadrature amplitude modulation (16-QAM) and 64-QAM microwave vector signal transmission experiments, measured error vector magnitudes (EVMs) are 4.14% and 4.38%, respectively, after 25-km fiber transmission, and the measured spurious-free dynamic range (SFDR) is 114.5 dB·Hz2/3, which shows a good performance in linearity.

Are you more risk-seeking when helping others? Effects of situational urgency and peer presence on prosocial risky behavior.

Introduction: Prosocial risky behavior (PRB) proposes that individuals take risks for others' benefits or social welfare, and that this may involve trade-offs between risk and social preferences. However, little is known about the underlying cognitive mechanisms of risk-seeking or aversion during PRB. Methods: This study adopted the dilemma-priming paradigm to examine the interaction between the risk levels of personal cost and situational urgency on PRB (Experiment 1, N = 88), and it further uncovered the modulation of the risk levels of failure (Experiment 2, N = 65) and peer presence (Experiment 3, N = 80) when helping others. Results: In Experiment 1, the participants involved in risky dilemmas made more altruistic choices for strangers in urgent situations compared to those for strangers in non-urgent situations. However, increasing the risk levels of personal cost decreased the frequencies of help offered to strangers in urgent situations. Experiment 2 further established that, similar to the risk of personal cost, increasing the risk levels of failure when helping others also decreased the frequencies of help offered to strangers in urgent situations. Furthermore, in dilemmas involving a low-risk personal cost, Experiment 3 showed that peer presence encouraged the participants to make more altruistic choices when providing help to strangers in non-urgent situations. Discussion: Individuals demonstrate obvious risk-seeking behavior when helping others and that both non-urgent situations and peer presence weaken the effect of increased risk aversion on PRB in a limited manner.

Mitochondrion-targeting and in situ photocontrolled protein delivery via photocages.

Defects in mitochondrial proteostasis contribute to many disorders, including cancer, neurodegeneration, and metabolic and genetic diseases. A strategy aimed at restoring the damaged mitochondrial proteostasis is the mitochondrion-targeting and carrier-free delivery of exogenous functional proteins that can replace the endogenous dysfunctional proteins. The modification of a protein with a photolabile protecting group (PPG, i.e., photocage group) can be activated in situ by response to illumination, leading to release of the protein from its photocage. Here, the Cys and peptide photocages with coumarin were first prepared and characterized for proof of concept. Then, we designed a pair of photocage groups PPG-RhB and PPG-TPP using coumarin and mitochondrion-targeting Rhodamine B (RhB) and triphenylphosphine (TPP), and another pair of organelle-nontarget photocage groups Br-PPG and NO2-PPG for comparison. The proteins modified with these two pairs of photocage groups undergo photolysis in solutions, and can penetrate cell membrane toward their destinations in the carrier-free fashions. The intracellular protein photocages are in situ activated by illumination at 405 nm, and the proteins are released from their photocages in mitochondria and cytoplasm, respectively. This strategy of light-responsive and carrier-free cellular delivery enables mitochondrial and cytoplasmic accumulation of exogenous proteins.