ASYMMETRIC LEAVES2-LIKE38, one member of AS2/LOB gene family, involves in regulating ab-adaxial patterning in Arabidopsis lateral organs

Abstract

ASYMMERTIC LEAVES1 (AS1) and AS2 in Arabidopsis are essential in determining leaf cell fates of adaxial axis. Here, we report ASYMMERTIC LEAVES2-LIKE38 (ASL38/LBD41), is an important gene of the LATERAL ORGAN BOUNDARY DOMAIN family. ASL38/LBD41 was detected in the adaxial and internal domain between the ab-adaxial domains of leaves. For explaining ASL38/LBD41 role in Arabidopsis development, a construct of the sense-expressing ASL38/LBD41 was transformed to Arabidopsis (Col-0); thus gained both overexpressing and cosuppressing 35S:ASL38/LBD41 plants. Rosette leaves of these overexpressing plants showed narrow (Class I) to radial symmetric needle-like patterns (Class II), compared with those of wild-type control, exhibiting adaxilized defect. However, rosette leaves of these cosuppressing plants showed narrow (Class I) to radial symmetric needle-like patterns (Class II), in contrast to those of wild-type (Col-0), exhibiting abaxilized defect. Furthermore, phenotypes observed in asl38-1 mutants suggest a redundant function for ASL38/LBD41 in boosting adaxial and/or inhibiting cell fate in abaxial axis. Together, our data suggest that ASL38/LBD41 might play a role of specialization in adaxial cell fate in Arabidopsis lateral organs.