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PHYTOCHROME INTERACTING FACTORS (PIFs) integrate light and temperature signs to control plant growth and development. However, little is known about PIFs in crop plants such as cotton. Here, we identified 68 PIF proteins and their coding genes from an allotetraploid and three diploid ancestors. Cotton PIFs contain typical ACTIVEPHYA-BINDING (APA) and ACTIVE PHYB-BINDING (APB) motifs by which they bind to phytochrome phyA and phyB, respectively, and have a BASIC HELIX-LOOP-HELIX (bHLH) domain and a nuclear localization sequence necessary for bHLH-type transcription factors. Bioinformatics analysis showed that the promoter of each PIF gene contains multiple cis-acting elements and that the evolution of cotton genomes probably underwent loss, recombination, and tandem replication. Further observations indicated that the sensitivity of cotton PIF expression to high temperature was significantly different from that to low temperature. We found that allotetraploid Gossypium hirsutum PIF4a (GhPIF4a) was induced by high temperature. GhPIF4a promotes flowering in cotton and Arabidopsis and binds to the promoter of GhFT (G. hirsutum FLOWERING LOCUS T), and binding increased with increasing temperature. Our work identifies the evolutionary and structural characteristics and functions of PIF family members in cotton.

Background Verticillium wilt of cotton is a serious disease caused by the infection of soil borne fungus Verticillium dahliae Kleb, but the infection mechanisms remain to be explored. Here, we investigated how phytohormones ethylene affected the infection of V. dahliae strain Vd991 on cotton (Gossypium hirsutum L.) cultivar YZ1. The precursor of ethylene biosynthesis is 1-aminocyclopropane-1-carboxylic acid (ACC), whose production in vivo depends on activation of ACC synthase (ACS). Results Preliminary observations indicated that ACC applications reduced the disease incidence, disease index and stem vascular browning by impeding fungal biomass accumulation. Transcriptome and qRT-PCR data disclosed that Vd991 induced GhACS2 and GhACS6 expression. GhACS2- or GhACS6-overexpressing transgenic YZ1 lines were created, respectively. In a Verticillium disease nursery, these ACC-accumulated transgenic plants showed decreased disease indexes, stem fungal biomasses and vascular browning. More importantly, these ACC-accumulating plants decreased the green fluorescent protein-marked Vd991 colonization and diffusion in root tissues. Further, either ACC treatment or ACC-accumulating cotton plants activated salicylic acid (SA)-dependent resistance responses. Conclusions The GhACS2- and GhACS6-denpendent ACC accumulations enhanced the resistance of cotton to V. dahliae in a SA-dependent manner, and this lays a foundation for cotton resistance breeding.

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Low expression of CTBP2 and CASP8AP2 correlated with poor outcome and predicted risk of relapse in pediatric B-cell acute lymphoblastic leukemia (B-ALL). This study aimed to investigate the molecular mechanism by which CASP8AP2 regulates LEF1 expression by interacting with CtBP2 and ZEB2 in Acute lymphoblastic lymphoma (ALL). There was an interaction between CASP8AP2, ZEB2, and CtBP2, and then the interaction between CtBP2 and ZEB2 was observed after downregulating the expression of CASP8AP2. The wild type (containing the ZEB2 binding site) or mutant (containing a mutant binding site) LEF1 gene promoter sequence was inserted into the pGL3-basic plasmid, and a dual-luciferase reporter gene detection system was used to observe how CASP8AP2, ZEB2, and CtBP2 regulate the transcription of the LEF1 gene. We conclude that CASP8AP2, CtBP2, and ZEB2 can all bind to the LEF1 gene promoter region and reduce the luciferase activity of the LEF1 promoter. Meanwhile, the interaction of ZEB2 and the LEF1 promoter was significantly weakened after downregulation of CASP8AP2. Knockdown of CASP8AP2 in the 697 cell lines resulted in the significant upregulation of the mRNA expression levels of the stemness-related genes CD44, JAG1, and SALL4. In conclusion, CASP8AP2 is vital for the interaction between CtBP2 and ZEB2, inhibiting LEF1 and stemness-related genes expression ALL. Supplemental data for this article is available online at https://doi.org/10.1080/08880018.2022.2033369 .

Plant root growth is controlled by auxin (IAA) and ethylene. The appropriate IAA concentration is regulated by many events, such as IAA biosynthesis, conjugation, and degradation. The levels of ethylene and its precursor 1-aminocyclopropane-1-carboxylic acid (ACC) depend on the activity of ACC synthases (ACSs). However, some questions have been raised: can ACS family members specifically regulate the ACC concentration in response to NaCl stress, and if so, how? How does ACC production affect IAA homeostasis during the root growth of Arabidopsis seedlings? Here, our observations showed that NaCl inhibition of root growth was greater in the ACS2-deficient mutants acs2-1 and acs2-2 because of the reduction of ACC and IAA accumulation in their root tips, while this reduction was rescued in transformants, including acs2 complementary (ACS2/acs2-1) and ACS2 overexpression (ACS2-OE) lines. The data showed that the decreased IAA levels resulted from increased activity of IAA conjugation enzymes, such as GH3.5 and GH3.9. These results suggest that ACS2 activity is an early response factor in the signaling pathway of NaCl-inhibited root growth.

To probe for factors that can be used effectively to predict the prognostic survival of patients with endometrial cancer recurrence.The clinicopathological data of 473 patients with stage Ⅰ to Ⅲ endometrial cancer who underwent standard surgical treatment from October 2013 to May 2019 were retrospectively collected, and post-operative recurrence of the patients were followed up. Overall recurrence includes local recurrence and poor prognosis recurrence. The endpoint indicators of this study are the recurrence-free survival (RFS) and overall survival (OS) of patients with overall recurrence, local recurrence, and poor prognosis recurrence (PPR). The Kaplan-Meier survival curve was used to evaluate the OS and RFS of patients. Cox proportional-hazards model was used to identify factors affecting the prognostic survival of patients with endometrial cancer recurrence.Among the 473 patients, 406 did not experience recurrence. A total of 67 patients, accounting for 14.2%, had recurrence. Among them, 27 had local recurrence, accounting for 5.7%, while 40 had poor prognosis recurrence, accounting for 8.5%. The median follow-up time of patients with recurrence was 38 months. The survival curve showed that the RFS and OS of the patients in the recurrence-free group remained unchanged, while the patients in the recurrence group, regardless of whether they had overall recurrence, local recurrence or PPR, experienced a decrease in RFS and OS(FIGO stage Ⅲ, increased Ki-67 expression, and decreased ER expression can increase patients' risk of postoperative recurrence, and FIGO stage Ⅲ and decreased expression of PR can increase the risk of death in patients with recurrence.

Aim: Dominant negative mutant G proteins have provided critical insight into the mechanisms of G protein-coupled receptor (GPCR) signaling, but the mechanisms underlying the dominant negative characteristics are not completely understood. The aim of this study was to determine the structure of the dominant negative Gαi1β1γ2 G203A/A326S complex (Gi-DN) and to reveal the structural basis of the mutation-induced phenotype of Gαi1β1γ2. Methods: The three subunits of the Gi-DN complex were co-expressed with a baculovirus expression system. The Gi-DN heterotrimer was purified, and the structure of its complex with GDP was determined through X-ray crystallography. Results: The Gi-DN heterotrimer structure revealed a dual mechanism underlying the dominant negative characteristics. The mutations weakened the hydrogen bonding network between GDP/GTP and the binding pocket residues, and increased the interactions in the Gα-Gβγ interface. Concomitantly, the Gi-DN heterotrimer adopted a conformation, in which the C-terminus of Gαi and the N-termini of both the Gβ and Gγ subunits were more similar to the GPCR-bound state compared with the wild type complex. From these structural observations, two additional mutations (T48F and D272F) were designed that completely abolish the GDP binding of the Gi-DN heterotrimer. Conclusion: Overall, the results suggest that the mutations impede guanine nucleotide binding and Gα-Gβγ protein dissociation and favor the formation of the G protein/GPCR complex, thus blocking signal propagation. In addition, the structure provides a rationale for the design of other mutations that cause dominant negative effects in the G protein, as exemplified by the T48F and D272F mutations.