Whole transcriptome analyses of six thoroughbred horses before and after exercise using RNA-Seq

Background: Thoroughbred horses are the most expensive domestic animals, and their running ability and knowledge about their muscle-related diseases are important in animal genetics. While the horse reference genome is available, there has been no large-scale functional annotation of the genome using expressed genes derived from transcriptomes. Results: We present a large-scale analysis of whole transcriptome data. We sequenced the whole mRNA from the blood and muscle tissues of six thoroughbred horses before and after exercise. By comparing current genome annotations, we identified 32,361 unigene clusters spanning 51.83 Mb that contained 11,933 (36.87%) annotated genes. More than 60% (20,428) of the unigene clusters did not match any current equine gene model. We also identified 189,973 single nucleotide variations (SNVs) from the sequences aligned against the horse reference genome. Most SNVs (171,558 SNVs; 90.31%) were novel when compared with over 1.1 million equine SNPs from two SNP databases. Using differential expression analysis, we further identified a number of exercise-regulated genes: 62 up-regulated and 80 down-regulated genes in the blood, and 878 up-regulated and 285 down-regulated genes in the muscle. Six of 28 previously-known exercise-related genes were over-expressed in the muscle after exercise. Among the differentially expressed genes, there were 91 transcription factor-encoding genes, which included 56 functionally unknown transcription factor candidates that are probably associated with an early regulatory exercise mechanism. In addition, we found interesting RNA expression patterns where different alternative splicing forms of the same gene showed reversed expressions before and after exercising. Conclusion: The first sequencing-based horse transcriptome data, extensive analyses results, deferentially expressed genes before and after exercise, and candidate genes that are related to the exercise are provided in this study.close151

Phosphorescent Ir(III) Complexes for Biolabeling and Biosensing

Cyclometalated Ir(III) complexes exhibit strong phosphorescence emission with lifetime of submicroseconds to several microseconds at room temperature. Their synthetic versatility enables broad control of physical properties, such as charge and lipophilicity, as well as emission colors. These favorable properties have motivated the use of Ir(III) complexes in luminescent bioimaging applications. This review examines the recent progress in the development of phosphorescent biolabels and sensors based on Ir(III) complexes. It begins with a brief introduction about the basic principles of the syntheses and photophysical processes of cyclometalated Ir(III) complexes. Focus is placed on illustrating the broad imaging utility of Ir(III) complexes. Phosphorescent labels illuminating intracellular organelles, including mitochondria, lysosomes, and cell membranes, are summarized. Ir(III) complexes capable of visualization of tumor spheroids and parasites are also introduced. Facile chemical modification of the cyclometalating ligands endows the Ir(III) complexes with strong sensing ability. Sensors of temperature, pH, CO2, metal ions, anions, biosulfur species, reactive oxygen species, peptides, and viscosity have recently been added to the molecular imaging tools. This diverse utility demonstrates the potential of phosphorescent Ir(III) complexes toward bioimaging applications.N

Achieving Long‐Wavelength Electroluminescence Using Two‐Coordinate Gold(I) Complexes: Overcoming the Energy Gap Law

Abstract Two‐coordinate coinage metal complexes have emerged as promising emitters for highly efficient organic light‐emitting devices (OLEDs). However, achieving efficient long‐wavelength electroluminescence emission from these complexes remains as a daunting challenge. To address this challenge, molecular design strategies aimed at bolstering the photoluminescence quantum yield (Φ) of Au(I) complex emitters in low‐energy emission regions are investigated. By varying amido ligands, a series of two‐coordinate Au(I) complexes is developed that exhibit photoluminescence peak wavelengths over a broad range of 533−750 nm. These complexes, in particular, maintain Φ values up to 10% even in the near‐infrared emission region, overcoming the constraints imposed by an energy gap. Quantum chemical calculations and photophysical analyses reveal the action of radiative control, which serves to overcome the energy gap law, becomes more pronounced as the overlap between hole and electron distributions (Sr(r)) in the excited state increases. It is further elucidated that Sr(r) increases with the distance between the hole‐distribution centroid and the nitrogen atom in an amido ligand. Finally, multilayer OLEDs involving the Au(I) complex emitters exhibit performances beyond the borderline of the electroluminescence wavelength−external quantum efficiency space set by previous devices of coinage metal complexes

Aggregation of an n-pi* Molecule Induces Fluorescence Turn-on

Although n-pi* molecules can serve as electroluminescent materials because of the harvesting of singlet and triplet excitons through El-Sayed-rule-allowed reverse intersystem crossing, the weak fluorescence emissions of such molecules have prevented applications into devices. We have discovered a 1 order of magnitude enhancement of the fluorescence of a prototypical n-pi* fluorophore, 7-phenylcoumarin (PC), upon aggregation. We performed a mechanistic study consisting of structural, photophysical, and quantum chemical investigations, and found that the aggregation positioned the fluorescent electronic state below the nonemissive tripletn-pi* transition state. Our studies, for the first time, demonstrate intramolecular geometry and intermolecular arrangements in the solid state to be significant factors in the photoluminescence quantum yields of n-pi* fluorophores

Aggregation of an <i>n</i>–π* Molecule Induces Fluorescence Turn-on

Although <i>n</i>–π* molecules can serve as electroluminescent materials because of the harvesting of singlet and triplet excitons through El-Sayed-rule-allowed reverse intersystem crossing, the weak fluorescence emissions of such molecules have prevented applications into devices. We have discovered a 1 order of magnitude enhancement of the fluorescence of a prototypical <i>n</i>–π* fluorophore, 7-phenylcoumarin (PC), upon aggregation. We performed a mechanistic study consisting of structural, photophysical, and quantum chemical investigations, and found that the aggregation positioned the fluorescent electronic state below the nonemissive triplet <i>n</i>–π* transition state. Our studies, for the first time, demonstrate intramolecular geometry and intermolecular arrangements in the solid state to be significant factors in the photoluminescence quantum yields of <i>n</i>–π* fluorophores

Substituent effects on the luminescence and charge transport properties of novel bis-lactam-based molecules

A series of bis-lactam-based molecules were synthesized and applied in organic field-effect transistors (OFETs) and organic light-emitting diodes (OLEDs). Among the derivatives, 1,5-dioctyl-3,7-bis(9-phenyl-9H-carbazol-2-yl)-1,5-naphthyridine-2,6-dione (NTD-pCz) exhibited the highest maximum hole mobility of 0.11 cm(2) V-1 s(-1) , with on-off current ratios (Ion/Ioff) of &gt; 105 in OFETs, which was attributed to NTD-pCz exhibiting the lowest reorganization energy, extended it-conjugation with a relatively small dihedral angle between the NTD core and the side group, and the strongest intermolecular interaction in the thin-film state. In addition, NTD-pCz exhibited the highest maximum external quantum efficiency of 3.56%, with a current efficiency of 9.95 cd A(-1), when incorporated into nondoped OLEDs, which is ascribed to its excellent solid-state photoluminescence quantum yield of 83%. These results reveal the potential of NTD-based molecules for use in efficient next generation multifunctional optoelectronic devices.N

Improving Electroluminescence of Two-Coordinate Au(I) Complexes: Insights into Steric and Electronic Control

This research elucidates the effects of structural modulations on electroluminescent Au(I) complexes, shedding light on factors governing radiative and nonradiative processes. A series of Au(I) complexes, fortified with ortho-substituents in carbene and amido ligands, are subjected to rigorous structural, photophysical, and quantum chemical investigations, which unveil distinct structural and electronic effects exerted by the ligands. The investigations reveal that nonradiative processes are governed primarily by the energy-gap law. Radiative processes are observed to have a weak correlation with the mutual interactions of the molecular orbitals of carbene and amido ligands. Rather, it is discovered that an accumulation of the negative charge in the Au 5d orbital in the excited state decelerates radiative processes. The effectiveness of these findings is substantiated through the larger external quantum efficiency of electroluminescence devices employing the Au(I) complex, in comparison to those based on the archetypical Au(I) complex and the organic thermally activated delayed fluorescent molecule. These compelling revelations underscore the untapped potential of Au(I) complexes in the advancement of electroluminescence technology and advocate for continued investigations into the intriguing domain of ligand structural control. Molecular factors that control photoluminescence efficiencies of two-coordinate Au(I) complexes involve the emission energy and the charge in the Au 5d-orbital.imag

High-performance blue OLED using multiresonance thermally activated delayed fluorescence host materials containing silicon atoms

Abstract We report three highly efficient multiresonance thermally activated delayed fluorescence blue-emitter host materials that include 5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene (DOBNA) and tetraphenylsilyl groups. The host materials doped with the conventional N 7,N 7,N 13,N 13,5,9,11,15-octaphenyl-5,9,11,15-tetrahydro-5,9,11,15-tetraaza-19b,20b-diboradinaphtho[3,2,1-de:1’,2’,3’-jk]pentacene-7,13-diamine (ν-DABNA) blue emitter exhibit a high photoluminescence quantum yield greater than 0.82, a high horizontal orientation greater than 88%, and a short photoluminescence decay time of 0.96–1.93 μs. Among devices fabricated using six synthesized compounds, the device with (4-(2,12-di-tert-butyl-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracen-7-yl)phenyl)triphenylsilane (TDBA-Si) shows high external quantum efficiency values of 36.2/35.0/31.3% at maximum luminance/500 cd m−2/1,000 cd m−2. This high performance is attributed to fast energy transfer from the host to the dopant. Other factors possibly contributing to the high performance are a T1 excited-state contribution, inhibition of aggregation by the bulky tetraphenylsilyl groups, high horizontal orientation, and high thermal stability. We achieve a high efficiency greater than 30% and a small roll-off value of 4.9% at 1,000 cd m−2 using the TDBA-Si host material