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Analysis of genetic differences underlying chilling stress tolerance using whole genome Re-Sequencing in walnut (Juglans regia L.).

Walnut (Juglans regia L.) is prized worldwide for both its nutritional value and economic importance, yet it remains vulnerable to cold stress, with significant differences in tolerance among varieties. This study combined physiological analyses with whole-genome resequencing (WGS) to evaluate the cold stress responses of two varieties, &#x2018;Qingxiang&#x2019; and &#x2018;Liaoning No.8&#x2019;. Under chilling stress (0&#xa0;&#xb0;C), we measured electrolyte leakage and antioxidant enzyme activity, applying both exogenous methyl jasmonate (MeJA) and the jasmonate inhibitor DIECA. Genomic variations were analyzed using WGS. Results showed that &#x2018;Liaoning No.8&#x2019; exhibited superior cold tolerance. Application of MeJA reduced electrolyte leakage by 37% and MDA accumulation by 52% on average, whereas DIECA exacerbated stress-related damage. WGS achieved 16.24&#x2013;16.26&#xd7; coverage and identified 2.73&#x2013;2.78&#xa0;million SNPs, 378&#x2013;382k InDels, 25&#x2013;26k SVs, and 7.2&#x2013;7.9k CNVs. Twenty genes containing sequence variants showed transcriptional responses under cold stress that were significantly correlated with mutation density (r&#x2009;=&#x2009;0.62, P&#x2009;<&#x2009;0.01). One gene, XM_018985465.2, which lacked SNPs in &#x2018;Liaoning No.8&#x2019;, was expressed 4.2 times more in this variety, suggesting cis-regulatory influence. These findings highlight the role of jasmonic acid signaling in enhancing cold tolerance in walnut and offer genomic insights into its underlying adaptive mechanisms.

Juglans

Engineering cold stress resilience in capsicum annuum through functional genomics and precision breeding.

This review synthesizes the molecular mechanisms of cold tolerance in pepper, integrating multi-omics data,genome editing, and precision breeding strategies to accelerate the development of cold-resilient cultivars. Cold stress is a significant environmental factor that affects the growth, productivity, and fruit quality of Capsicum annuum by impairing membrane integrity photosynthesis and cellular redox homeostasis. Although pepper has several endogenous cold-responsive regulators such as CaNAC035 and CabHLH035, along with antioxidant defense systems, its cold tolerance remains limited due to low transcriptional activation of key regulators, functional redundancy among cold-responsive genes, and the polygenicity of cold tolerance. These complexities, combined with low genetic diversity and linkage drag, have hindered the improvement of cold-resistant cultivars through conventional breeding. This review brings together the recent progress in understanding the molecular mechanisms of cold stress perception, signal transduction, transcriptional regulation, metabolic reprogramming, and phytohormone interactions in pepper. Precision Breeding 2.0 is a new innovation that combines the integration of multi-omics-based target identification with next-generation genome-editing techniques, allowing precise and multiplex engineering of complex and interconnected regulatory networks instead of single genes. We cover new approaches such as engineering the DREB/CBF pathway, allele-specific editing and targeted disruption of negative regulators to enhance the pathway(s) involved in cold response. Moreover, we propose a roadmap for integration of transcriptomics, proteomics, metabolomics, high-throughput phenomics, and speed breeding to accelerate the identification, validation, and deployment of superior alleles to boost cold tolerance. This review provides a foundation for developing climate-resilient pepper cultivars by connecting functional genomics with precision genome engineering approaches to maintain productivity under variable environmental conditions.

Capsicum

Modes of thermal protection in polar bear cubs--at birth and on emergence from the den.

At birth in late December the polar bear is small (700 g), uninsulated, and helpless. It probably has a modest capacity for metabolic heat production and depends on the female and a snow den in which it is born for thermal protection. The microclimate of an artificial polar bear den was investigated at Point Barrow, AK, and the temperature therein found to stay around 0 degrees C provided a heat source (200 W) equivalent to an adult polar bear was introduced. When the bears desert the den in early April the cub has grown to about 10 kg and has a well-developed fur insulation, but almost no subcutaneous fat. The cub has a high resting metabolic rate (4.6 W.kg-1), which is supported by the fat polar bear milk. Its lower critical temperature is about -30 degrees C, and an ambient temperature of -45 degrees C results in only a 33% increase in metabolism. The cub can tolerate a wind chill of 2.3 kW.m2 without apparent stress of drop in rectal temperature. If the cub is immersed in ice water rectal temperature drops 11 degrees C in 30 min. It is concluded that the cub can tolerate extremely low temperatures in air due to fur insulation and high metabolic heat production, but is unable to cope with the chill of ice water for any prolonged period of time.

Adipose Tissue

Integrative analysis of transcriptome and chromatin accessibility reveals promoter-proximal regulation and identifies candidate ABC transporters associated with cold stress responses in maize.

BACKGROUND: Low-temperature stress is a formidable environmental constraint that severely limits the growth and productivity of maize (Zea mays L.), particularly during the highly vulnerable early seedling stage. While cold tolerance is a critical agronomic objective, the integrated transcriptional and epigenetic regulatory mechanisms that govern this trait remain largely elusive. Characterizing these coordinated molecular networks is fundamental to the genetic enhancement of cold resilience in maize. METHODS: Using two maize inbred lines contrasting in chilling response (ZHB12 tolerant, B73 sensitive), we performed integrative time&#x2011;course RNA&#x2011;seq and ATAC&#x2011;seq to thoroughly and systematically characterize the precise dynamic interplay between gene expression and chromatin accessibility under cold stress conditions at the seedling stage. RESULTS: Physiological assessments confirmed that ZHB12 possesses superior cold tolerance, manifested by significantly attenuated electrolyte leakage and reduced foliar damage compared to B73. Transcriptomic profiling revealed a massive, time-dependent divergence in gene expression between the two genotypes, with a major regulatory transition identified at 24&#xa0;h of cold exposure. Functional enrichment analysis demonstrated that ZHB12 preferentially activates a robust defense repertoire, including Photosystem II electron transport, diterpenoid biosynthesis, and ATP biosynthetic pathways. Notably, multiple ATP-binding cassette (ABC) transporter genes were coordinately upregulated under chilling, suggesting their potential involvement in cellular homeostasis. ATAC-seq analysis indicated that cold stress is associated with chromatin remodeling in ZHB12, with increased accessibility observed in proximal promoter regions. Integrative analysis identified a core set of dual-responsive genes, in which increased promoter accessibility coincided with transcriptional upregulation. These genes were predominantly enriched in transporter activity and transcriptional regulation, suggesting potential epigenetic link to the superior stress response of ZHB12. CONCLUSION: Our findings reveal extensive transcriptional and chromatin accessibility changes in ZHB12 under cold stress. The observed associations between promoter accessibility and gene activation, particularly in genes involved in transport processes, highlight candidate regulators potentially contributing to cold tolerance. This study provides a molecular framework and identifies high-value candidate genes that may inform future efforts in breeding cold-tolerant maize, pending functional validation.

Zea mays

Phase I study of iv administration of methanol extraction residue of Bacillus Calmette-Guérin.

Four weekly iv doses, ranging from 10 to 640 microgram/m2, of the methanol extraction residue of bacillus Calmette-Guérin (MER) were given to 22 patients with advanced cancer in an effort to determine a maximum tolerated dose. Fever and chills for 24-48 hours were common at doses greater than 80 microgram/m2 but were prolonged for 3 days to 9 weeks at 640 microgram/m2. While moderate decreases in pulmonary vital capacity were seen at all dose levels, diffusing capacity decreased consistently only at higher doses. However, no roentgenographic changes suggestive of multiple lung granulomas were observed, such as were produced in dogs and mice by iv administration of MER. Autopsy failed to reveal granulomas in three patients. There were no objective tumor responses, nor were consistent changes observed in blood counts or skin tests to recall antigens. MER can be given iv with acceptable acute toxicity in doses up to 640 microgram/m2, at which point fever may be unduly prolonged. Patients given MER iv must be followed carefully for the development of interstitial pneumonitis.

Adult

A preliminary study of intravenous methanol extraction residue of BCG in treatment of advanced cancer.

Twenty-four patients with advanced cancer not reacting to conventional therapy were treated with 97 courses of i.v. MER (methanol extraction residue of BCG). MER was administered by i.v. infusion over a 4-h period, twice a week, in dosages varying from 0.05 mg to 1.25 mg. The skin reactivity to 5 recall antigens was evaluated in the patients. All patients except 4 were anergic. Twelve patients had no side-effects. Anergic patients had less side-effects than ergic patients. The side-effects recorded in the others were fever, chills, vomiting and tachycardia. The reaction subsided within 24 h after treatment and was tolerable for most patients. In 2 patients an objective improvement was observed. No changes in cutaneous reactivity, renal and hepatic functions were found. A significant increase in peripheral leucocyte count was noted in two patients and slight a increase in the remainder.

Adult

Phase I study with neocarzinostatin: tolerance to two hour infusion and continuous infusion.

Neocarzinostatin (NCZ), an acidic polypeptide antibiotic, was given to 47 patients with cancer and leukemia, and tolerance to two schedules, a single dose given as a 2 hour infusion and a continuous infusion over 5 days was investigated. Immediate reactions, including fever, chills, rigor, hypertension and mental confusion, were dose-limiting for the 2 hour infusion schedule, occurring at 3000 U/m2 and higher. Continuous administration for 5 days eliminated the immediate reactions and then hematological toxicity--often prolonged leukopenia and thrombocytopenia--became dose-limiting. Other toxicities of NCZ at both dose schedules included anemia, fever and chills, anorexia, nausea and vomiting, hepatic dysfunction, azotemia, hypophosphatemia, aminoaciduria, stomatitis, phlebitis and/or cellulitis at the venous infusion site and pruritus. Patients with solid tumors who had received little or no prior chemotherapy and had good bone marrow reserve tolerated up to 6000 U/m2/24 hours X 5 days. One patient with previously treated acute myelocytic leukemia was induced into a good partial remission lasting 10 weeks.

Adolescent

[Clinical experiences with a 6% hydroxyethyl starch 40000 solution; metabolic parameters and tolerance].

A 6% hycroxyethyl starch solution with a mean molecular weight of 40 000 and a degree of substitution of 0.5--0.55 was tested under controlled conditions at 79 clinics in West Germany. The following parameters were evaluated: tolerance, circulation effectiveness, influence on serum electrolytes, hemoglobin and hematocrit. A total of 779 patients received either 6% HES 40 000 alone, 6% HES 40 000 and electrolyte solution or 6% HES 40 000 solution and other volume effective plasma substitutes for treatment of hypovolemia. The results show that stable circulation can be achieved in 4 to 6 hours during narcosis as well as in the subsequent phase with a sufficient supply of fluid through 6% HES 40 000 solution. One case of flush and a slight chill were reported as side effects related to the hydroxyethyl starch.

Fever