barren inflorescence2 Encodes a co-ortholog of the PINOID serine/threonine kinase and is required for organogenesis during inflorescence and vegetative development in maize.
Organogenesis in plants is controlled by meristems. Axillary meristems, which give rise to branches and flowers, play a critical role in plant architecture and reproduction. Maize (Zea mays) and rice (Oryza sativa) have additional types of axillary meristems in the inflorescence compared to Arabidopsis (Arabidopsis thaliana) and thus provide an excellent model system to study axillary meristem initiation. Previously, we characterized the barren inflorescence2 (bif2) mutant in maize and showed that bif2 plays a key role in axillary meristem and lateral primordia initiation in the inflorescence. In this article, we cloned bif2 by transposon tagging. Isolation of bif2-like genes from seven other grasses, along with phylogenetic analysis, showed that bif2 is a co-ortholog of PINOID (PID), which regulates auxin transport in Arabidopsis. Expression analysis showed that bif2 is expressed in all axillary meristems and lateral primordia during inflorescence and vegetative development in maize and rice. Further phenotypic analysis of bif2 mutants in maize illustrates additional roles of bif2 during vegetative development. We propose that bif2/PID sequence and expression are conserved between grasses and Arabidopsis, attesting to the important role they play in development. We provide further support that bif2, and by analogy PID, is required for initiation of both axillary meristems and lateral primordia.
McSteen
Paula
P
Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA. pcm11@psu.edu
Malcomber
Simon
S
Skirpan
Andrea
A
Lunde
China
C
Wu
Xianting
X
Kellogg
Elizabeth
E
Hake
Sarah
S
D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000737:chemistry; D004251:DNA Transposable Elements; D035263:Flowering Tops / Q000254:growth & development* / Q000378:metabolism; D015870:Gene Expression; D007210:Indoleacetic Acids / Q000378:metabolism; D018519:Meristem / Q000254:growth & development; D008969:Molecular Sequence Data; D038081:Organogenesis / Q000235:genetics*; D006109:Poaceae / Q000201:enzymology / Q000235:genetics / Q000254:growth & development*; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D029681:Arabidopsis Proteins; D004251:DNA Transposable Elements; D007210:Indoleacetic Acids; C405165:PINOID protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases