Study of the UTR regions in the regulation of the SHORTROOT

GIGENA V.; REINHEIMER R.

Congreso; SAIB 2022; 2022

In the field of plant biology, the mechanisms that gave rise to Kranz anatomy and, with it, the emergence of C4 photosynthesis, is still one unsolved mystery. We seek to study the molecular mechanisms responsible for the diversification of leaf anatomies of plants. In particular, the aim of this work is to increase the knowledge about the role of the SHORTROOT gene (SHR) that is known to be influencing the maize foliar anatomy and development of the Kranz bundle sheath cells. We know that SHR has multiple copies in grasses, however, little is known about the function of these copies during leaf development. Based on sequence comparison we identified highly conserved motifs along the 5’UTR and this motivated us to explore whether such regions affect the levels of SHR expression. To achieve this, we cloned the 5’UTR sequence of SHR between the constitutive 35S CaMV promoter and the GUS reporter gene and used this to agroinfiltrate tobacco leaves. We observed that the detection of GUS protein on samples varied in correlation with differences observed in the 5’UTR of SHR copies. These results suggest that 5’UTR of SHR have gene regulation elements that control the expression pattern of each copy. In consequence, the study of the 5’UTR region may bring us closer to understanding the SHR mode of action in leaf development and differentiation of Kranz anatomy.