Immunolocalization of some arabinogalactan protein epitopes during indirect somatic embryogenesis and shoot organogenesis in leaf culture of centaury (Centaurium erythraea Rafn)

Abstract

Common centaury (Centaurium erythraea Rafn) is a medicinal plant of great importance for both pharmaceutical and food industries. Distribution of arabinogalactan proteins (AGPs) with specific epitopes recognized by seven monoclonal antibodies (mAbs) was investigated during indirect somatic embryogenesis (ISE) and shoot organogenesis (ISO) in centaury leaf culture. Dynamic changes were observed in localization of JIM4, JIM8, JIM13, JIM15, LM2, LM14, and MAC207 epitopes during somatic embryo (SE) and adventitious bud (AB) development. AGPs responded to all tested mAbs and expressed in numerous meristematic centers that were formed on leaf explants. In globular SEs, the distribution pattern of JIM4, JIM13, JIM15, LM2, and MAC207 epitopes was observed, while during the progression of somatic embryo development, the number of detected AGPs decreased. During formation of ABs, the number of detected AGPs also decreased. In fully formed ABs, only JIM4 and MAC207 were detected. The present study suggests JIM13 antibody as a marker for ISE in centaury leaf culture. These results implicated that AGPs were developmentally regulated during centaury ISE and ISO.