In addition to enhancing ongoing phylogenetic and conservation research, this assembly will enable investigations of the genetic basis of adaptations including drought tolerance and fire resilience. These traits, which are ecological hallmarks of manzanitas, are of growing importance in the context of the increased drought and fire frequency and intensity that are occurring in California as a result of climate change. This assembly can also serve as a reference for studying the diversification and population genetics of Arctostaphylos, which may shed light on aspects of diversification in other complex groups of the CFP. Arctostaphylos is the third genus with a genome assembly in the heath family, Ericaceae, following release of assembled genome sequences of Rhododendron and Vaccinium . These two genera are of significant economic importance: many species, hybrids, and cultivars of Rhododendron, including rhododendron and azalea, are important landscape and ornamental plants, and the fruits of many Vaccinium species, which include cranberry, blueberry, and huckleberry, are consumed by humans and other animals. Species in the Ericaceae are also notable for their ability to tolerate acidic and nutrient-poor soils that often characterize boreal forests and bogs, allowing them to thrive in habitats that are inaccessible to most species. Their tolerance for these conditions is due in part to the formation of mutualistic associations between the roots of the plants and soil fungi of a type unique to the heath family known as ericoid mycorrhizae. Ericoid mycorrhizae are distinct from common mycorrhizal associations found in most angiosperms,square pots and are far less well understood .

Complete genome sequences from three genera in this family will provide a strong foundation for investigating the basis of this unique mutualism and its ability to promote survival in inhospitable soils. The size of the A. glauca assembly is 547Mb, which is similar to the two Rhododendron genomes and half that of V corymbosum, which is tetraploid . The tetraploid nature of V.corymbosum also explains the vastly greater number of duplicated genes in its assembly compared to the two diploid assemblies. The scaffold N50 of the A.glauca assembly is longer than R.williamsianum, and close to R.simsii and V.corymbosum, suggesting that the contiguity of Arctostaphylos is comparable to the other taxa . Analysis using RepeatModeler indicated that 57.71% of the A. glauca genome is composed of different categories of repetitive elements . In contrast, analysis using RepeatModeler identified only 26%, 47.5%, and 44.3% of the genome comprising repeat elements in R. williamsianum, R. simsii, and V. corymbosum respectively. The BUSCO completeness assessment of the A. glauca assembly is higher than R. williamsianum and close to the V. corymbosum , indicating that our final assembly is high quality . Overall, the A. glauca, R. simsii and V. corymbosum genomes are of comparably high contiguity and completeness. The lower contiguity and completeness of the R. williamsianum genome may be due to the lack of HiFi or other long read data in the assembly. This explanation is consistent with other studies demonstrating improved assembly with the inclusion of longer reads . Although the big berry manzanita is a common and widespread species, nearly half of the 60+ manzanita species are rare or threatened.

Many are now represented by only one or two populations, and are thus vulnerable to complete eradication by the increasingly common and intense wildfires experienced across California each year. Our manzanita genome sequence will help fulfill the overall goal of the CCGP, serving as a key resource to assess genetic diversity in these threatened endemics and move forward with coordinated conservation programs.According with the International Diabetes Federation , the prevalence of people with T2DM raised from 108 million to 537 million in the last 40 years. T2DM is a disease caused by the incapacity of the cells to respond to insulin effects. This disease is strongly linked with obesity resulting from the excess of body weight and sedentarism . Obesity is considered a complex chronic progressive disease defined as abnormal or excessive adipose tissue accumulation caused by an imbalance of energy intake and energy expenditure that leads to mild, chronic, systemic inflammation. Diet is the main risk factor that contributes to obesity . In a cross-sectional study from 2015 in Canadian adults, it was reported that ultra-processed food consumption, which contributed to 24-73% of total daily energy intake, was associated with higher prevalence of obesity in the studied population . It was also reported that high fat diets and elevated intake of red meat as well as high sugar intake impairs health causing obesity and increase the risk of noncommunicable diseases such as type 2 diabetes mellitus , dementia, myocardial infarction, stroke, hypertension, fatty liver disease and cancer . In general, obesity is associated with a lower life quality and expectancy by an estimated of 5-20 years depending on the severity and NCD’s . Adipose tissue has a crucial role on systemic energy balance , playing an essential role in maintaining lipid and glucose homeostasis. The fat stored as triglycerides tends to accumulate in the subcutaneous and visceral depots, incrementing their size and producing hypertrophy, hyperplasia, and systemic metabolic dysfunction . The main mechanism believed to link obesity with T2DM is insulin resistance derived from adipose tissue accompanied by impaired insulin secretion by β-cells in the pancreas. Free fatty acids stimulate NF-κB and P38 MAPK signaling pathway through MyD88 and TRIF mediated downstream pathways with a subsequent activation of TLR4 expression in adipocytes and macrophages, increasing ER stress and producing ROS, promoting the secretion of proinflammatory cytokines, causing the initial step of low-grade systemic inflammation .

The pro-inflammatory adipokines secreted by adipose tissue are monocyte chemotactic protein- 1 , tumor necrosis factor α , interleukin 1-β , and interleukin-6 . The potential cellular mechanisms of obesity-induced insulin resistance start with increased systemic TNF-α which stimulates the activity of IKK, p38 MAPK, JNK, and PKC, insulin receptor substrate ; impairing tyrosine phosphorylation and increasing the risk of insulin resistance in adipose tissues, muscles, and liver . Lifestyle modifications with controlled calorie intake, healthy diet and increased physical activity are considered the fundamental basis of a successful treatment . Higher protein intake, foods with a low glycemic index and lower fat consumption may help diabetic patients . Moreover, recent studies suggest that the intake of fresh fruits and vegetables is related with a lower incidence of T2DM. In a randomized controlled trial, it has been explained and demonstrated how diets rich in fruits and vegetables can improve blood glucose and insulin secretion . Furthermore, studies also indicate that bio-active compounds present in fruits, vegetables, spices, legumes, edible flowers, mushrooms, and medicinal plants, are prospective candidates for the prevention and the control of T2DM . Fruits and vegetables are rich sources of bio-active compounds, particularly polyphenols, exerting numerous positive human health effects. Polyphenols are plant secondary metabolites that act as a defense against pathogens, diseases, predators,large plastic pots ultraviolet radiation, parasites, and oxidants . Polyphenols are widely used in the food industry as a natural antioxidant ingredient in foods by their effects on preventing lipid oxidation and oxidative rancidity . Polyphenols are classified as flavonoids and non-flavonoids; flavonoids are divided in 12 groups including, flavonols, flavanols, flavons, flavan-3-ols, anthocyanins, flavanones, isoflavones, and dihydrochalcone. Non-flavonoids include phenolic acids, lignans and stilbenes. Following intake of polyphenols, they undergo important metabolism , which start in the enterocytes of small and large intestines before being absorbed into the circulation. Once in the hepatocytes, the hydroxyl group in the flavonoids undertake glucuronidation, methylation and sulfation to be available to enter in blood circulation. The next step is their flux to all organs and finally their elimination through urine. In the large intestine, the colonic microbiota will produce an extensive breakdown of the original polyphenolic structure into a phenolic metabolites with low-molecular-weight, this will produce a better absorbability of the compounds, and its passage to the secondary phase metabolism .Anthocyanins are hydrophilic pigments contained in red, violet, and blue colors of fruits and vegetables. Most abundant anthocyanins are glycosylated forms of cyanidin, delphinidin, malvidin, peonidin, petunidin, and pelargonidin. Anthocyanins are commonly linked to a sugar molecule, frequently glucose, nevertheless, rhamnose, galactose, and rutinose can also be present. Anthocyanins play an important role in obesity and diabetes prevention. Different studies have suggested that, once absorbed, anthocyanins can positively modulate GLUT4 in skeletal muscle and adipose tissue; other authors conclude that these phytochemicals may affect gastrointestinal microbiota and impact the host health . One of the foods rich in anthocyanins are BB. The seed color of BB is determined mainly by the presence of anthocyanins, and condensed tannins .

As one of the main flavonoid groups found in BB, anthocyanins have been shown to determine the color of the seed coats, but also demonstrated to be biologically active and have potential health properties . BB have been suggested to contribute to the treatment of T2DM. Anthocyanins from BB have a strong antioxidant ability to arrest free radicals along with anti-inflammatory activity . We previously showed through an in silico perspective, that polyphenols found in BB, particularly anthocyanins, could modulate the activity of proteins involved in different mechanisms of T2DM pathways . Molecular docking results highlighted that cyanidin 3-glucoside, delphinidin 3-glucoside, and petunidin 3-glucoside had a stronger affinity for 11β- HS, GFAT, PPARG, PTP, RTKs, and PTP, proteins related with mechanisms that can regulate different biomarkers linked to inflammation, insulin resistance, oxidative stress, glucose and lipid metabolism, insulin secretion, and carbohydrate absorption . The mode of action underlying the anthocyanin biological effects has been attributed only to their direct antioxidant properties. However in recent years, it has been shown that these bio-active compounds exert more complex molecular mechanisms of action, including modulation of gene expression, cell signaling, or DNA methylation . Taken together, the aim of this study was to characterize anti-diabetic properties of an anthocyanin-rich extract from BB and decipher, using RNAseq approach, molecular mechanisms of action of these bio-active compounds on adipose tissue in a diabetic rat model. We previously reported the chemical composition of BB extract . Polyphenol extraction from BB was performed on recently harvested BB which were finely ground until obtaining a flour consistency. The flour was mixed with a solution of ethanol and hydrochloric acid . The mix was stirred for 4 h at room temperature and covered from light. The extracts were centrifuged for 20 min at 13,000 rpm, the supernatant collected and evaporated at 38◦C and 90 rpm until ethanol was completely removed. The extracts were stored at −20◦C overnight and lyophilized during three days at −50◦C and 250 mBar. The polyphenolic powders were conserved at 4◦C until their use . The animal experiments were approved by the Internal Committee of Care and Use of Laboratory Animals of the Center for Research and Assistance in Technology and Design of the State of Jalisco, A.C., according with the Official Mexican Standard NOM-062-ZOO- 1999, concerning the technical specifications for the production, care and use of laboratory animals and NOM-087-ECOLSSA1-2002, related to the Management of Infectious Biological Hazardous Waste -RBPI. In addition, the Standard Bioterial Operation Procedure and the Animal Experimentation Laboratory Regulations were applied. A total of 24 male Wistar rats around 150 ± 20g were purchased from Envigo RMS S.A de C.V. and placed in a SPF barrier environment under standard environmental conditions under 12 h light/dark cycle, with free access to water and standard diet during the acclimation stage. After 2 weeks of acclimatization, all the rats were randomly divided into three groups , namely the HE , BB , and DB animals with induced T2DM without treatment . During the experiment the HE group was fed with standard diet, while BB and DB groups were fed with a high fat diet  consisting of 42.7% carbohydrates, 42% lipids and 15.2% proteins. After the HFD feeding for 5 weeks, the rats were fasted for 12 h with unlimited access to water. Rats from HE group received an intraperitoneal injection of citrate buffer. Our T2DM induction is supported by the methodology reported by Skovsko, , where the prolonged administration of HFD combined with a single low dose of Streptozotocin produce a partial damage of pancreatic B-cells accompanied by lipotoxicity, glucolipotoxicity, insulin resistance, and hyperinsulinemia caused by HFD. Rats in BB and DB groups received an intraperitoneal injection of a single low dose of Streptozotocin, N–α- D-glucosamine  solution dissolved in sodium citrate buffer .