The transcription factor OsbZIP48 governs rice responses to zinc deficiency.

Zinc (Zn) deficiency is the most prevalent micronutrient disorder in rice and leads to delayed development and decreased yield. Nevertheless, despite its primary importance, how rice responds to Zn deficiency remains poorly understood. This study presents genetic evidence supporting the crucial role of OsbZIP48 in regulating rice's response to Zn deficiency, consistent with earlier findings in the model plant Arabidopsis. Genetic inactivation of OsbZIP48 in rice seedlings resulted in heightened sensitivity to Zn deficiency and reduced Zn translocation from roots to shoots. Consistently, OsbZIP48 was constitutively expressed in roots, slightly induced by Zn deficiency in shoots and localized into nuclei induced by Zn deficiency. Comparative transcriptome analysis of the wild-type plants and osbzip48 mutant grown under Zn deficiency enabled the identification of OsbZIP48 target genes, including key Zn transporter genes (OsZIP4 and OsZIP8). We demonstrated that OsbZIP48 controlled the expressions of these genes by directly binding to their promoters, specifically to the Zn deficiency response element motif. This study establishes OsbZIP48 as a critical transcription factor in rice's response to Zn deficiency, offering valuable insights for developing Zn-biofortified rice varieties to combat global Zn limitation.

Zinc transporter genes and urological cancers: integrated analysis suggests a role for ZIP11 in bladder cancer.

Although zinc transporters were shown to play roles in the development of prostate, bladder, and renal cancer, no study has evaluated the genetic variants in zinc transporter genes with risk of urological cancers. A candidate gene association study using genome-wide association study (GWAS) datasets was conducted for variants in 24 zinc transporter genes. Genotypes were analyzed using logistic regression models adjusted for covariates. The function of identified variants was assessed by using the Encyclopedia of DNA Elements (ENCODE). We further evaluated tumors for somatic change of the implicated gene(s) and the associations between identified variants and patient survival from data in The Cancer Genome Atlas (TCGA). A ZIP11 variant, rs8081059, was significantly associated with increased risk of renal cell carcinoma (odds ratios (OR) = 1.28, 95 % confidence intervals (CI) (1.13-1.45), p = 0.049). No zinc transporter variants were associated with prostate cancer risk. Four variants within ZIP11 were significantly associated with bladder cancer risk: rs11871756 (OR = 1.43, 95 % CI (1.24-1.63), p = 0.0002), rs11077654 (OR = 0.76, 95 % CI (0.68-0.85), p = 0.001), rs9913017 (OR = 0.76, 95 % CI (0.68-0.85), p = 0.002), and rs4969054 (OR = 0.78, 95 % CI (0.69-0.88), p = 0.02); the three protective variants were co-located and highly correlated. These variants were located within predicted transcribed or enhancer regions. Among the 253 bladder cancer patients in TCGA, two had tumors that contained deleterious missense mutations in ZIP11. Moreover, rs11077654 was significantly associated with survival of bladder cancer patients (p = 0.046). In conclusion, zinc transporter gene, ZIP11, may play an important role in bladder cancer. Further studies of the gene are warranted.

Foliar zinc reduced Cd accumulation in grains by inhibiting Cd mobility in the xylem and increasing Cd retention ability in roots1.

Cadmium (Cd) pollution endangers the safe utilization of paddy soils, and foliar zinc (Zn) can reduce the toxic effects of Cd. However, little is known about the effects of foliar Zn application on the transport and immobilization of Cd in key rice tissues and the physiological state of rice plants. A pot experiment was conducted to explore the effects of spraying 0.2% and 0.4% Zn (ZnSO4) during the early grain-filling stage on Cd transport in rice, photosynthesis, glutathione (GSH) levels, Cd concentrations in xylem sap, and the expression of Zn transporter genes. The results showed that grain Cd concentrations in the 0.2% Zn and 0.4% Zn treatments were 24% and 31% lower, respectively, than those of the control treatments at maturity. Compared with the control treatments, the 0.4% Zn treatment increased Cd by 60%, 69%, 23%, and 22% in husks, rachises, first internodes, and roots, respectively. Application of Zn reduced xylem Cd content by up to 26% and downregulated transporter genes (OSZIP12, OSZIP4, and OSZIP7a) in flag leaves. Foliar Zn increased Cd bioaccumulation in roots while decreasing Cd bioaccumulation in grains. Zn reduced GSH concentration in flag leaves and stems, inhibiting photosynthesis (intercellular CO2 concentration, transpiration rate). Taken together, foliar Zn can reduce the expression of Zn transporter genes and the mobility of Cd in the xylem, promoting the fixation of Cd in husks, rachises, first internodes, and roots, ultimately reducing Cd concentration in rice grains.

Zinc-bearing zeolite clinoptilolite improves tissue zinc accumulation in laying hens by enhancing zinc transporter gene mRNA abundance.

A study was conducted to investigate effects of zinc-bearing zeolite clinoptilolite (ZnCP), as an alternative for zinc sulfate (ZnSO4), on laying performance, tissue Zn accumulation and Zn transporter genes expression in laying hens. Hy-Line Brown laying hens were allocated to three treatments, each of which had six replicates with 15 hens per replicate, receiving basal diet supplemented with ZnSO4 (control, 80 mg Zn/kg diet), 0.23% ZnCP (40.25 mg Zn/kg diet) and 0.46% ZnCP (80.50 mg Zn/kg diet) for 8 weeks, respectively. Compared with control, hens fed diet containing 0.23% ZnCP had similar Zn content in measured tissues (P > 0.05). A higher ZnCP inclusion (0.46%) enhanced Zn accumulation in liver (P < 0.05) and pancreas (P < 0.05). In addition, ZnCP inclusion increased blood iron (Fe) content (P < 0.05). ZnCP supplementation enhanced jejunal metallothionein-4 (MT-4) messenger RNA (mRNA) abundance (P < 0.05). ZnCP inclusion at a higher level (0.46%) increased mRNA expression of MT-4 in pancreas (P < 0.05) and zinc transporter-1 (ZnT-1) in jejunum (P < 0.05). The highest ZnT-2 mRNA abundance in jejunum was found in hens fed 0.23% ZnCP inclusion diet (P < 0.05). The results indicated that ZnCP reached a higher bioavailability as compared with ZnSO4 as evidenced by enhanced tissue Zn accumulation and Zn transporter genes expression.