Relation of down-regulation of METTL10 and podocyte injury

doi:10.3969/j.issn.1674-8115.2021.10.003

Abstract

Abstract: Objective

·To identify the differentially expressed genes (DEGs) in podocyte injury and validate the expression of METTL10, one of these critical genes.

Methods

·The microarray expression profile of a podocyte injury model, dataset GSE108629, was downloaded from the GEO database, containing 4 normal podocyte samples and 4 injured podocyte samples, and the DEGs were diagnosed using the limma software package and affy software package (|log FC| ≥ 2 and adjusted P value<0.05). Patients with significant proteinuria who underwent renal biopsy and were diagnosed as focal segmental glomerulosclerosis or minimal change disease were retrospectively enrolled. Control group was patients who underwent renal biopsy and were proven as slight pathological changes or benign arteriolar neophrosclerosis. The general and clinical data were collected, and the expression of METTL10 in renal tissue was detected by immunofluorescence staining. Adriamycin (ADR)-induced nephropathy mouse model was established by a single intravenous injection of ADR into BAL/BC mouse. Mice were randomly divided into two groups: control group (treated with the same volume of PBS) and ADR group (treated with ADR 10 mg/kg body weight). On Day 0 and Day 14, urine was collected for 24 h using a metabolic cage and urinary albumin creatinine ratio (UACR) of mice were detected; on Day 15, mice were sacrificed and kidney tissue was collected. The expression of METTL10 and podocyte marker proteins like synaptopodin, nephrin, podocin, and Wilms' tumor 1 (WT1) in kidneys from ADR-treated mouse model was analyzed by Western blotting.

Results

·A total of 5 353 genes were significantly differentially expressed in injured podocytes compared with intact podocytes, among which 3 402 DEGs were up-regulated and 1 951 DEGs were down-regulated. METTL10 was found to be one of those that overe significantly down-regulated. Immunofluorescence staining indicated that METTL10 was expressed in normal human glomeruli and METTL10 was colocalized with podocalyxin, one of podocyte specific markers. Additionally, METTL10 was low expressed in the renal biopsy specimens from patients with significant proteinuria compared with that in the control group. On Day 14 after administration of ADR, mice developed significant proteinuria, shown by UACR detection (P=0.005); Western blotting revealed that METTL10 was significantly down-regulated (P=0.001), along with the significantly decreased expression of synaptopodin (P=0.001), nephrin (P=0.005), podocin (P=0.000) and WT1 (P=0.006) in ADR-treated mice compared with that in normal mice. The differences of the expression of METTL10 and the above podocyte markers between these two groups were statistically significant.

Conclusion

·The down-regulation of METTL10 may be involved in podocyte injury.

Key words: podocyte injury, proteinuria, METTL10, differentially expressed genes (DEGs)

CLC Number:

R692

Ji-wen BAO, Zi-yang LI, Huan-zhen YAO, Bei WU, Wen-yan ZHOU, Le-yi GU, Ling WANG. Relation of down-regulation of METTL10 and podocyte injury[J]. JOURNAL OF SHANGHAI JIAOTONG UNIVERSITY (MEDICAL SCIENCE), 2021, 41(10): 1290-1296.

Figures/Tables 8

Fig 1 Identification of DEGs in injured podocytes shown by the volcanoplot

Fig 2 Heatmap for the top50 of DEGs in injured podocytes

Fig 3 Changes of METTL10 mRNA level in damaged podocytes

Tab 1 Demographic and baseline characteristics of control group and patients with massive proteinuria

Item	Control group （n=3）	Significant proteinuria group（n=3）
Age/year	41.67±10.73	31.00±2.52
Gender/n
Male	2	2
Female	1	1
Blood pressure/mmHg
Systolic	125.70±9.39	126.70±10.04
Diastolic	80.33±5.04	82.67±3.71
sCr/（μmol·L^-1）	109.00±24.21	67.80±6.90
eGFR/［mL·（min·1.73m²）^-1］	71.00±19.86	113.70±0.88
Urine protein for 24 h/g	0.41±0.21	7.17±2.42^①

Fig 4 Immunofluorescence staining for detection of METTL10 expression in glomerula (×400)

Fig 5 Change of UACR in the two groups

Fig 6 Expression of podocyte markers in kidney tissue of mice (n=6)

Fig 7 Expression of METTL10 protein in kidney tissue of mice (n=6)

TrendMD

References 29

1	Eckardt K U, Coresh J, Devuyst O, et al. Evolving importance of kidney disease: from subspecialty to global health burden[J]. Lancet, 2013, 382(9887): 158-169.
2	Guo Y, Pace J, Li Z, et al. Podocyte-specific induction of Krüppel-like factor 15 restores differentiation markers and attenuates kidney injury in proteinuric kidney disease[J]. J Am Soc Nephrol, 2018, 29(10): 2529-2545.
3	Zhou LT, Cao YH, Lv LL, et al. Feature selection and classification of urinary mRNA microarray data by iterative random forest to diagnose renal fibrosis: a two-stage study[J]. Sci Rep, 2017, 7: 39832.
4	Cechova S, Dong F, Chan F, et al. MYH9 E1841K mutation augments proteinuria and podocyte injury and migration[J]. J Am Soc Nephrol, 2018,29(1): 155-167.
5	Yamamoto-Nonaka K, Koike M, Asanuma K, et al. Cathepsin D in podocytes is important in the pathogenesis of proteinuria and CKD[J]. J Am Soc Nephrol, 2016, 27(9): 2685-2700.
6	Kriz W, Lemley KV. A potential role for mechanical forces in the detachment of podocytes and the progression of CKD[J]. J Am Soc Nephrol, 2015, 26(2): 258-269.
7	Nagata M. Podocyte injury and its consequences[J]. Kidney Int, 2016, 89(6): 1221-1230.
8	Perico L, Conti S, Benigni A, et al. Podocyte-actin dynamics in health and disease[J]. Nat Rev Nephrol, 2016, 12(11): 692-710.
9	Blaine J, Dylewski J. Regulation of the actin cytoskeleton in podocytes[J]. Cells, 2020, 9(7): 1700.
10	Torban E, Braun F, Wanner N, et al. From podocyte biology to novel cures for glomerular disease[J]. Kidney Int, 2019, 96(4): 850-861.
11	Yu SM, Nissaisorakarn P, Husain I, et al. Proteinuric kidney diseases: a podocyte's slit diaphragm and cytoskeleton approach[J]. Front Med (Lausanne), 2018, 5: 221.
12	Wang WN, Zhang WL, Zhou GY, et al. Prediction of the molecular mechanisms and potential therapeutic targets for diabetic nephropathy by bioinformatics methods[J]. Int J Mol Med, 2016, 37(5): 1181-1188.
13	Butz H, Szabó PM, Nofech-Mozes R, et al. Integrative bioinformatics analysis reveals new prognostic biomarkers of clear cell renal cell carcinoma[J]. Clin Chem, 2014, 60(10): 1314-1326.
14	Lay AC, Barrington AF, Hurcombe JA, et al. A role for NPY-NPY2R signaling in albuminuric kidney disease[J]. Proc Natl Acad Sci U S A, 2020,117(27): 15862-15873.
15	Falnes PØ, Jakobsson ME, Davydova E, et al. Protein lysine methylation by seven-β-strand methyltransferases[J]. Biochem J, 2016, 473(14): 1995-2009.
16	Li Z, Gonzalez PA, Sasvari Z, et al. Methylation of translation elongation factor 1A by the METTL10-like See1 methyltransferase facilitates tombusvirus replication in yeast and plants[J]. Virology, 2014, 448: 43-54.
17	Lipson RS, Webb KJ, Clarke SG. Two novel methyltransferases acting upon eukaryotic elongation factor 1A in Saccharomyces cerevisiae[J]. Arch Biochem Biophys, 2010, 500(2): 137-143.
18	Hellwege JN, Velez ED, Giri A, et al. Mapping eGFR loci to the renal transcriptome and phenome in the VA Million Veteran Program[J]. Nat Commun, 2019, 10(1): 3842.
19	Rane MJ, Zhao Y, Cai L. Krϋppel-like factors (KLFs) in renal physiology and disease[J]. EBioMedicine, 2019, 40: 743-750.
20	卢甜美, 杜玄一. 足细胞损伤机制研究进展[J]. 现代医学, 2017,45(2):311-314.
21	Zhou LT, Qiu S, Lv LL, et al. Integrative bioinformatics analysis provides insight into the molecular mechanisms of chronic kidney disease[J]. Kidney Blood Press Res, 2018, 43(2): 568-581.
22	尚懿纯, 曹式丽, 窦一田, 等. 局灶节段性肾小球硬化足细胞损伤生物标志物的研究进展[J]. 安徽医科大学学报, 2017,52(1):151-154.
23	Jefferson JA, Shankland SJ. The pathogenesis of focal segmental glomerulosclerosis[J]. Adv Chronic Kidney Dis, 2014, 21(5): 408-416.
24	Liapis H, Romagnani P, Anders HJ. New insights into the pathology of podocyte loss: mitotic catastrophe[J]. Am J Pathol, 2013, 183(5): 1364-1374.
25	Garg P. A review of podocyte biology[J]. Am J Nephrol, 2018,47:3-13.
26	Akram Z, Ahmed I, Mack H, et al. Yeast as a model to understand actin-mediated cellular functions in mammals-illustrated with four actin cytoskeleton proteins[J]. Cells, 2020, 9(3): 672.
27	Snape N, Li D, Wei T, et al. The eukaryotic translation elongation factor 1A regulation of actin stress fibers is important for infectious RSV production[J]. Virol J, 2018,15(1):182.
28	Gross SR. Actin binding proteins: their ups and downs in metastatic life[J]. Cell Adh Migr, 2013, 7(2): 199-213.
29	Li F, Mao X, Zhuang Q, et al. Inhibiting 4E-BP1 re-activation represses podocyte cell cycle re-entry and apoptosis induced by adriamycin[J]. Cell Death Dis, 2019, 10(3): 241.

[1]	GU Ting, JIANG Bo-Ren, HAN Bing, YANG Li-Zhen. Study on the correlation between body composition and renal damage indexes in patients with type 2 diabetes mellitus [J]. , 2016, 36(06): 866-.
[2]	CHEN Jue, ZHANG Lu-lu, YAN Yu-cheng, et al. Effects of rapamycin on podocytes of rats with diabetic nephropathy [J]. , 2013, 33(9): 1197-.
[3]	WANG Li-hua, GU Le-yi, LIANG Xin-yue, et al. Effects of Rapamycin on nephropathy and expression of VEGF and VEGF receptors in PAN nephritic mice [J]. , 2010, 30(4): 375-.