TIGHT JUNCTION PROTEIN GENE EXPRESSION OF THE INSTESTINES OF THE BRAZILIAN FREE-TAILED BAT

FERNÁNDEZ MARINONE ; BRUN A; TAVERNELLI L; CHEDIACK JG; GATICA-SOSA CP; KARASOV WH; CAVIEDES-VIDAL E1

San Luis

Congreso; CUYO BIOLOGY SOCIETY; 2012

Sociedad de Biologia de Cuyo

Recently it has been demonstrated that flying mammals primarily absorb water-soluble solutes in the intestines using the paracellular route [across tight junctions (TJ) between adjacent enterocytes], while non-flying mammals mainly use the transcellular route (across cell membrane using transporter proteins). The aim of this study is to present a preliminary comparison of the gene expression of TJ proteins between the insectivore bat Tadarida brasiliensis and pre- viously reported data from mice by Holmes and collaborators (2006). Claudins 1, 2, 4, 5, 12, 15, occludin, ZO-1 and JAM mRNAs were quantified by RT-qPCR using Eef1a1 and β-actin as refer- ence genes from three sections of the intestine (proximal, medial and distal to the pyloric valve) of the bat. The comparison of the TJ protein RNAs profiles between bats and mice was performed to explore a potential molecular basis for the observed difference in paracellular absorption. Higher values of claudins 1 and 5 were found in all sections of the intestine of the bat, though these pro- teins are postulated to diminish leakiness through TJ. On the con- trary, claudin 2, which forms pores, was increased in bats in the midgut, compared with mice, giving molecular support to the ob- served higher paracellular absorption in bats compared to mice.