Sexual plant reproduction depends on the production and differentiation of functional gametes by the haploid gametophyte generation. Currently, we have a limited understanding of the regulatory mechanisms that have evolved to specify the gametophytic developmental programs. To unravel such mechanisms, it is necessary to identify transcription factors (TF) that are part of such haploid regulatory networks. Here we focus on bZIP TFs that have critical roles in plants, animals and other kingdoms. We report the functional characterization of Arabidopsis thaliana AtbZIP34 that is expressed in both gametophytic and surrounding sporophytic tissues during flower development. T-DNA insertion mutants in AtbZIP34 show pollen morphological defects that result in reduced pollen germination efficiency and slower pollen tube growth both in vitro and in vivo. Light and fluorescence microscopy revealed misshapen and misplaced nuclei with large lipid inclusions in the cytoplasm of atbzip34 pollen. Scanning and transmission electron microscopy revealed defects in exine shape and micropatterning and a reduced endomembrane system. Several lines of evidence, including the AtbZIP34 expression pattern and the phenotypic defects observed, suggest a complex role in male reproductive development that involves a sporophytic role in exine patterning, and a sporophytic and/or gametophytic mode of action of AtbZIP34 in several metabolic pathways, namely regulation of lipid metabolism and/or cellular transport.

• MeSH
• Arabidopsis genetika   metabolismus   MeSH
• buněčná stěna metabolismus   ultrastruktura   MeSH
• fluorescenční mikroskopie MeSH
• geneticky modifikované rostliny MeSH
• květy genetika   růst a vývoj   metabolismus   MeSH
• metabolické sítě a dráhy genetika   fyziologie   MeSH
• mikroskopie elektronová rastrovací MeSH
• mutace MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• proteiny huseníčku genetika   fyziologie   MeSH
• pyl genetika   metabolismus   ultrastruktura   MeSH
• pylová láčka genetika   růst a vývoj   metabolismus   MeSH
• regulace genové exprese u rostlin MeSH
• stanovení celkové genové exprese MeSH
• testy genetické komplementace MeSH
• trans-aktivátory genetika   fyziologie   MeSH
• transmisní elektronová mikroskopie MeSH
• vývojová regulace genové exprese MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bZIP34 protein, Arabidopsis MeSH Prohlížeč
• proteiny huseníčku MeSH
• trans-aktivátory MeSH