Identification of murine and human XCP1 genes as C/EBP-ε-dependent members of FIZZ/Resistin gene family

Serum concentrations of resistin-like molecules β and γ are elevated in high-fat-fed and obese db/db mice, with increased production in the intestinal tract and bone marrow

“…RELMβ mRNA and protein were abundant in the colon, and to a lesser extent in the ileum. On the other hand, RELMγ mRNA was abundant in the colon, ileum, bone marrow, spleen, pancreas and fat, consistent with previous reports [18][19][20] (Fig. 2a, lower panel).…”

“…The highest level of RELMβ expression was observed in goblet cells of the colon, consistent with previous reports [15,24], and RELMγ protein was also shown to be localised in goblet cells. In the bone marrow, about 30% of haematopoietic cells were stained with the anti-RELMγ antibody and these cells were myelocytes and metamyelocytes or neutrophils (data not shown), consistent with previous reports [19,20].…”

“…Injecting RELMβ reportedly induced insulin resistance in rats [16]. RELMγ is expressed in the colon, bone marrow, spleen and lung [17][18][19] and reportedly increases the proliferation rate of promyelocytic cells and modulates their differentiation [18]. RELMγ is also expressed in rat nasal respiratory epithelium, and is altered by cigarette smoke [17].…”

“…RELMγ reportedly binds α-defensin, a cysteine rich 3-4-kDa antimicrobial peptide stored in the cytoplasimic granules of neutrophils, some macrophages and intestinal Paneth cells [19]. Thus, it is possible that some protein(s), like α-defensin, which bind to RELMγ, also bind to RELMβ and may form polymers with disulphide bonds.…”

“…Finally, RELMγ/FIZZ4/XCP1 , a fourth member of the RELM/FIZZ/XCP family, was identified as a gene with decreased expression in rat nasal respiratory epithelium exposed to cigarette smoke [17]. RELMγ was expressed in the bone marrow, spleen, pancreas and colon, and was revealed to play a role as a cytokine in haematopoiesis [18,19].…”