In this study, ntamiR166a*, nta-miRn66 and nta-miRn52 were markedly induced by topping. Since topping is considered as wounding stress , it is easy to understand the changes in expression of miRNAs involved in response to stress. 9 miRNA families may be involved in N metabolism. NtamiRn73 targets nitrate transporter. Inorganic nitrogen is a vital nutrient for plants. Plants take up and assimilate both nitrate and ammonium with nitrate being the predominant form in most agricultural soils. Nitrate is taken up by roots then transported into cells via transporters from the NRT1 and NRT2 family of nitrate transporters . In the study, nta-miRn73 was markedly repressed by topping, which means that topping can promote roots to take up nitrate, and the result is consistent with the previous report . Nta-miRn51 targets methylmalonate-semialdehyde dehydrogenase which participates in 3 metabolic pathways: inositol metabolism, valine, leucine and isoleucine degradation, and propanoate metabolism. It has been proved that MMSDH may play a role in root development and leaf sheath elongation in rice . In this study, nta-miRn51 was markedly induced by topping. Nta-miR394a targets AAA-type ATPase family protein which plays an important role in protein unfoldase activity, including the dissociation of protein complexes . MK-1775 Glutamine-tRNA ligase is the target of nta-miRn19, which is related to amino acid metabolism. Nta-miRn27a targets ubiquitin family protein which participates in the degradation of protein. In this study, ntamiRn19, nta-miRn27a and nta-miR394a were significantly repressed by topping. Nta-miR398 targets U2 snRNP auxiliary factor large subunit. The poly -limiting element restricts the length of the poly tail to,20 nt when present in the terminal exon of a pre-mRNA. U2AF may have a role in PLE regulation of poly tail length . Nta-miRn39 targets protease inhibitor which inhibits the degradation of proteins. Elongation factor 1-alpha is the target of miRn393b*. EF-1-alpha participates in protein biosynthesis. Branched-chain amino acid transaminase 3 is the target of nta-miRn24. BCAT3 has the dual role in amino acid and glucosinolate biosynthesis . In this study, nta-miR398, nta-miRn39, nta-miRn24 and nta-miRn393b* were markedly induced by topping. Over the last decade discoveries in the metabolism field, starting with the association of increased tumor necrosis factor alpha and other inflammatory cytokines in obesity, have demonstrated the strong inflammatory underpinnings of PLX-4720 obesity and associated metabolic diseases . Obesity leads to elevated production of pro-inflammatory molecules such as TNF-a, IL-6, IL-1b, and MCP-1 in experimental murine models and in humans, notably in adipose tissue .