Author
JOHNSTON, R - Cornell University | |
WANG, M - Cornell University | |
SUN, Q - Cornell University | |
SYLVESTER, A - University Of Wyoming | |
Hake, Sarah | |
SCANLON, M - Cornell University |
Submitted to: The Plant Cell
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 12/18/2014 Publication Date: 12/26/2014 Citation: Johnston, R., Wang, M., Sun, Q., Sylvester, A.W., Hake, S.C., Scanlon, M. 2014. Transcriptomic analyses indicate that maize ligule development recapitulates gene expression patterns that occur during lateral organ initiation. The Plant Cell. 26:4718-4732. Interpretive Summary: We used laser microdissection and RNA sequencing to identify genes that are differentially expressed in discrete cell/tissue-specific domains along the proximal-distal axis of wild-type leaf primordia undergoing ligule initiation and compared transcript accumulation in wild-type and liguleless1-R mutant leaf primordia. We identified transcripts that are specifically upregulated at the blade-sheath boundary. A surprising number of these "ligule genes" have also been shown to function during leaf initiation or lateral branching and intersect multiple hormonal signaling pathways. Technical Abstract: Development of multicellular organisms proceeds via the correct interpretation of positional information to establish boundaries that separate developmental fields with distinct identities. The maize (Zea mays) leaf is an ideal system to study plant morphogenesis as it is subdivided into a proximal sheath and a distal blade, each with distinct developmental patterning. Specialized ligule and auricle structures form at the blade-sheath boundary. The auricles act as a hinge, allowing the leaf blade to project at an angle from the stem, while the ligule comprises an epidermally derived fringe. Recessive liguleless1 mutants lack ligules and auricles and have upright leaves. From detailed transcriptome analysis, we propose that genetic modules utilized in leaf and/or branch initiation are redeployed to regulate ligule outgrowth from leaf primordia. |