A QTL GN1.1, encoding FT-L1, regulates grain number and yield by modulating polar auxin transport in rice.

Rice grain number is a crucial agronomic trait impacting yield. In this study, we characterized a quantitative trait locus (QTL), GRAIN NUMBER 1.1 (GN1.1), which encodes a Flowering Locus T-like1 (FT-L1) protein and acts as a negative regulator of grain number in rice. The elite allele GN1.1B, derived from the Oryza indica variety, BF3-104, exhibits a 14.6% increase in grain yield compared with the O. japonica variety, Nipponbare, based on plot yield tests. We demonstrated that GN1.1 interacted with and enhanced the stability of ADP-ribosylation factor (Arf)-GTPase-activating protein (Gap), OsZAC. Loss of function of OsZAC results in increased grain number. Based on our data, we propose that GN1.1B facilitates the elevation of auxin content in young rice panicles by affecting polar auxin transport (PAT) through interaction with OsZAC. Our study unveils the pivotal role of the GN1.1 locus in rice panicle development and presents a novel, promising allele for enhancing rice grain yield through genetic improvement.

Dysfunction of duplicated pair rice histone acetyltransferases causes segregation distortion and an interspecific reproductive barrier.

Postzygotic reproductive isolation, which results in the irreversible divergence of species, is commonly accompanied by hybrid sterility, necrosis/weakness, or lethality in the F1 or other offspring generations. Here we show that the loss of function of HWS1 and HWS2, a couple of duplicated paralogs, together confer complete interspecific incompatibility between Asian and African rice. Both of these non-Mendelian determinants encode the putative Esa1-associated factor 6 (EAF6) protein, which functions as a characteristic subunit of the histone H4 acetyltransferase complex regulating transcriptional activation via genome-wide histone modification. The proliferating tapetum and inappropriate polar nuclei arrangement cause defective pollen and seeds in F2 hybrid offspring due to the recombinant HWS1/2-mediated misregulation of vitamin (biotin and thiamine) metabolism and lipid synthesis. Evolutionary analysis of HWS1/2 suggests that this gene pair has undergone incomplete lineage sorting (ILS) and multiple gene duplication events during speciation. Our findings have not only uncovered a pair of speciation genes that control hybrid breakdown but also illustrate a passive mechanism that could be scaled up and used in the guidance and optimization of hybrid breeding applications for distant hybridization.

Optimization of rice panicle architecture by specifically suppressing ligand-receptor pairs.

Rice panicle architecture determines the grain number per panicle and therefore impacts grain yield. The OsER1-OsMKKK10-OsMKK4-OsMPK6 pathway shapes panicle architecture by regulating cytokinin metabolism. However, the specific upstream ligands perceived by the OsER1 receptor are unknown. Here, we report that the EPIDERMAL PATTERNING FACTOR (EPF)/EPF-LIKE (EPFL) small secreted peptide family members OsEPFL6, OsEPFL7, OsEPFL8, and OsEPFL9 synergistically contribute to rice panicle morphogenesis by recognizing the OsER1 receptor and activating the mitogen-activated protein kinase cascade. Notably, OsEPFL6, OsEPFL7, OsEPFL8, and OsEPFL9 negatively regulate spikelet number per panicle, but OsEPFL8 also controls rice spikelet fertility. A osepfl6 osepfl7 osepfl9 triple mutant had significantly enhanced grain yield without affecting spikelet fertility, suggesting that specifically suppressing the OsEPFL6-OsER1, OsEPFL7-OsER1, and OsEPFL9-OsER1 ligand-receptor pairs can optimize rice panicle architecture. These findings provide a framework for fundamental understanding of the role of ligand-receptor signaling in rice panicle development and demonstrate a potential method to overcome the trade-off between spikelet number and fertility.

Transsphenoidal surgery for prolactinomas in male patients: a retrospective study.

Male patients with prolactinomas usually present with typical hyperprolactinemia symptoms, including sexual dysfunction and infertility. However, clinical factors related to sexual dysfunction and surgical outcomes in these patients remain unclear. This study aimed to investigate the outcomes of male patients with prolactinomas after transsphenoidal surgery and the risk factors affecting sexual dysfunction. This study was conducted on 58 male patients who underwent transsphenoidal surgery for prolactinomas between May 2014 and December 2020 at the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China. We evaluated the sexual function of patients before and after surgery through International Index of Erectile Function-5 scores, libido, and frequency of morning erection. Of the 58 patients, 48 (82.8%) patients had sexual intercourse preoperatively. Among those 48 patients, 41 (85.4%) patients presented with erectile dysfunction. The preoperative International Index of Erectile Function-5 scores in patients with macroprolactinomas were significantly higher than those in patients with giant prolactinomas (17.63 ± 0.91 vs 13.28 ± 1.43; P = 0.01). Postoperatively, the incidence of erectile dysfunction was 47.9%, which was significantly lower than that preoperatively (85.4%; P = 0.01). Twenty-eight (68.3%) patients demonstrated an improvement in erectile dysfunction. Tumor size and invasiveness were significantly correlated with the improvement of erectile dysfunction. Preoperative testosterone <2.3 ng ml-1 was an independent predictor of improvement in erectile dysfunction. In conclusion, our results indicated that tumor size and invasiveness were important factors affecting the improvement of sexual dysfunction in male patients with prolactinoma. The preoperative testosterone level was an independent predictor related to the improvement of erectile dysfunction.

An α/ß hydrolase family member negatively regulates salt tolerance but promotes flowering through three distinct functions in rice.

Ongoing soil salinization drastically threatens crop growth, development, and yield worldwide. It is therefore crucial that we improve salt tolerance in rice by exploiting natural genetic variation. However, many salt-responsive genes confer undesirable phenotypes and therefore cannot be effectively applied to practical agricultural production. In this study, we identified a quantitative trait locus for salt tolerance from the African rice species Oryza glaberrima and named it as Salt Tolerance and Heading Date 1 (STH1). We found that STH1 regulates fatty acid metabolic homeostasis, probably by catalyzing the hydrolytic degradation of fatty acids, which contributes to salt tolerance. Meanwhile, we demonstrated that STH1 forms a protein complex with D3 and a vital regulatory factor in salt tolerance, OsHAL3, to regulate the protein abundance of OsHAL3 via the 26S proteasome pathway. Furthermore, we revealed that STH1 also serves as a co-activator with the floral integrator gene Heading date 1 to balance the expression of the florigen gene Heading date 3a under different circumstances, thus coordinating the regulation of salt tolerance and heading date. Notably, the allele of STH1 associated with enhanced salt tolerance and high yield is found in some African rice accessions but barely in Asian cultivars. Introgression of the STH1HP46 allele from African rice into modern rice cultivars is a desirable approach for boosting grain yield under salt stress. Collectively, our discoveries not only provide conceptual advances on the mechanisms of salt tolerance and synergetic regulation between salt tolerance and flowering time but also offer potential strategies to overcome the challenges resulted from increasingly serious soil salinization that many crops are facing.

The Influence of Host Aphids on the Performance of Aphelinus asychis.

The aphid parasitoid Aphelinus asychis Walker is an important biological control agent against many aphid species. In this study, we examined whether the rearing host aphid species (the pea aphid, Acyrthosiphon pisum and the grain aphid, Sitobion avenae) affect the performance of A. asychis. We found that A. pisum-reared A. asychis showed a significantly larger body size (body length and hind tibia length) and shorter developmental time than S. avenae-reared A. asychis. There was no difference in the sex ratio between them. The longevity of A. pisum-reared A. asychis was also significantly longer than that of S. aveane-reared A. asychis. Furthermore, A. pisum-reared A. asychis presented stronger parasitic capacity and starvation resistance than S. aveane-reared A. asychi. In addition, host aphid alteration experiments showed that A. asychis only takes two generations to adapt to its new host. Taken together, these results revealed that A. pisum is a better alternative host aphid for mass-rearing and releasing of A. asychis. The body size plasticity of A. asychis is also discussed.

A genetic module at one locus in rice protects chloroplasts to enhance thermotolerance.

How the plasma membrane senses external heat-stress signals to communicate with chloroplasts to orchestrate thermotolerance remains elusive. We identified a quantitative trait locus, Thermo-tolerance 3 (TT3), consisting of two genes, TT3.1 and TT3.2, that interact together to enhance rice thermotolerance and reduce grain-yield losses caused by heat stress. Upon heat stress, plasma membrane-localized E3 ligase TT3.1 translocates to the endosomes, on which TT3.1 ubiquitinates chloroplast precursor protein TT3.2 for vacuolar degradation, implying that TT3.1 might serve as a potential thermosensor. Lesser accumulated, mature TT3.2 proteins in chloroplasts are essential for protecting thylakoids from heat stress. Our findings not only reveal a TT3.1-TT3.2 genetic module at one locus that transduces heat signals from plasma membrane to chloroplasts but also provide the strategy for breeding highly thermotolerant crops.

A rice QTL GS3.1 regulates grain size through metabolic-flux distribution between flavonoid and lignin metabolons without affecting stress tolerance.

Grain size is a key component trait of grain weight and yield. Numbers of quantitative trait loci (QTLs) have been identified in various bioprocesses, but there is still little known about how metabolism-related QTLs influence grain size and yield. The current study report GS3.1, a QTL that regulates rice grain size via metabolic flux allocation between two branches of phenylpropanoid metabolism. GS3.1 encodes a MATE (multidrug and toxic compounds extrusion) transporter that regulates grain size by directing the transport of p-coumaric acid from the p-coumaric acid biosynthetic metabolon to the flavonoid biosynthetic metabolon. A natural allele of GS3.1 was identified from an African rice with enlarged grains, reduced flavonoid content and increased lignin content in the panicles. Notably, the natural allele of GS3.1 caused no alterations in other tissues and did not affect stress tolerance, revealing an ideal candidate for breeding efforts. This study uncovers insights into the regulation of grain size though metabolic-flux distribution. In this way, it supports a strategy of enhancing crop yield without introducing deleterious side effects on stress tolerance mechanisms.

UDP-glucosyltransferase regulates grain size and abiotic stress tolerance associated with metabolic flux redirection in rice.

Grain size is an important component trait of grain yield, which is frequently threatened by abiotic stress. However, little is known about how grain yield and abiotic stress tolerance are regulated. Here, we characterize GSA1, a quantitative trait locus (QTL) regulating grain size and abiotic stress tolerance associated with metabolic flux redirection. GSA1 encodes a UDP-glucosyltransferase, which exhibits glucosyltransferase activity toward flavonoids and monolignols. GSA1 regulates grain size by modulating cell proliferation and expansion, which are regulated by flavonoid-mediated auxin levels and related gene expression. GSA1 is required for the redirection of metabolic flux from lignin biosynthesis to flavonoid biosynthesis under abiotic stress and the accumulation of flavonoid glycosides, which protect rice against abiotic stress. GSA1 overexpression results in larger grains and enhanced abiotic stress tolerance. Our findings provide insights into the regulation of grain size and abiotic stress tolerance associated with metabolic flux redirection and a potential means to improve crops.

A binary sampling Res2net reconstruction network for single-pixel imaging.

The traditional algorithm for compressive reconstruction has high computational complexity. In order to reduce the reconstruction time of compressive sensing, deep learning networks have proven to be an effective solution. In this paper, we have developed a single-pixel imaging system based on deep learning and designed the binary sampling Res2Net reconstruction network (Bsr2-Net) model suitable for binary matrix sampling. In the experiments, we compared the structural similarity, peak signal-to-noise ratio, and reconstruction time using different reconstruction methods. Experimental results show that the Bsr2-Net is superior to several deep learning networks recently reported and closes to the most advanced reconstruction algorithms.