Establishing a Framework for the Ad/Abaxial Regulatory Network of <i>Arabidopsis</i>: Ascertaining Targets of Class III HOMEODOMAIN LEUCINE ZIPPER and KANADI Regulation

Reinhart, Brenda J.; Liu, Tie; Newell, Nicole R.; Magnani, Enrico; Huang, Tengbo; Kerstetter, Randall A.; Michaels, Scott D.; Barton, Matt

doi:10.1105/tpc.113.111518

Cited by 94 publications

(97 citation statements)

References 77 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, while the function of other polarity determinants in promoting either adaxial or abaxial fate is conserved, their input into the regulation of YABBY genes must have diverged during plant evolution. Many more targets acting downstream of the core polarity network have recently been identified in Arabidopsis (Reinhart et al, 2013;Merelo et al, 2013;Iwasaki et al, 2013;Huang et al, 2014;Xie et al, 2015) and it will be interesting to see the extent to which these are conserved.…”

Section: The Molecular Genetics Of Leaf Polaritymentioning

confidence: 99%

“…For instance, the Arabidopsis HD-ZIPIII and KAN proteins have opposite effects on a common set of direct and indirect targets, most notably genes in the auxin pathway ( Fig. 5; Reinhart et al, 2013;Merelo et al, 2013;Huang et al, 2014;Xie et al, 2015). Although the precise contributions of auxin to leaf polarity remain unclear, the current data points to a role for auxin signaling at the adaxial-abaxial boundary, where it may coordinate the flattened outgrowth of the leaf blade in conjunction with the YABBY and WOX1 transcription factors known to drive this process (Eshed et al, 2004;Heisler et al, 2005;Wang et al, 2011;Nakata et al, 2012).…”

Section: Cellular Properties Of the Adaxial-abaxial Polarity Networkmentioning

confidence: 99%

See 1 more Smart Citation

The Sussex signal: insights into leaf dorsiventrality

Kuhlemeier

Timmermans

2016

Development

View full text Add to dashboard Cite

The differentiation of a leaf -from its inception as a semicircular bulge on the surface of the shoot apical meristem into a flattened structure with specialized upper and lower surfaces -is one of the most intensely studied processes in plant developmental biology. The large body of contemporary data on leaf dorsiventrality has its origin in the pioneering experiments of Ian Sussex, who carried out these studies as a PhD student in the early 1950s. Here, we review his original experiments in their historical context and describe our current understanding of this surprisingly complex process. Finally, we postulate possible candidates for the 'Sussex signal' -the elusive meristem-derived factor that first ignited interest in this important developmental problem.

show abstract

Section: The Molecular Genetics Of Leaf Polaritymentioning

confidence: 99%

Section: Cellular Properties Of the Adaxial-abaxial Polarity Networkmentioning

confidence: 99%

The Sussex signal: insights into leaf dorsiventrality

Kuhlemeier

Timmermans

2016

Development

View full text Add to dashboard Cite

show abstract

“…RA1 (Feurtado et al 2011). Evidence for combinatorial action of IDD genes in developmental patterning has recently emerged (Welch et al 2007;Reinhart et al 2013;Slewinski 2013), including novel roles in lateral organ development via regulation of auxin biosynthesis and transport (Cui et al 2013). One possibility is that RA1 may modulate auxin levels and distribution in the developing inflorescence indirectly via regulation of IDD genes.…”

Section: Common Targets Of Ra1 and Knotted1 Link Meristem Determinacymentioning

confidence: 99%

Regulatory modules controlling maize inflorescence architecture

et al. 2013

View full text Add to dashboard Cite

Genetic control of branching is a primary determinant of yield, regulating seed number and harvesting ability, yet little is known about the molecular networks that shape grain-bearing inflorescences of cereal crops. Here, we used the maize (Zea mays) inflorescence to investigate gene networks that modulate determinacy, specifically the decision to allow branch growth. We characterized developmental transitions by associating spatiotemporal expression profiles with morphological changes resulting from genetic perturbations that disrupt steps in a pathway controlling branching. Developmental dynamics of genes targeted in vivo by the transcription factor RAMOSA1, a key regulator of determinacy, revealed potential mechanisms for repressing branches in distinct stem cell populations, including interactions with KNOTTED1, a master regulator of stem cell maintenance. Our results uncover discrete developmental modules that function in determining grass-specific morphology and provide a basis for targeted crop improvement and translation to other cereal crops with comparable inflorescence architectures.

show abstract

“…Hence, loss-of-function mutations in genes promoting adaxial cell identity typically cause an abaxialized phenotype that correlates with the ectopic expression of abaxial genes, whereas loss-of-function mutations in abaxial genes produce an adaxialized phenotype that is accompanied by the expanded expression of adaxial genes. This antagonistic interaction between adaxial and abaxial factors may be mediated by mutually antagonistic regulation (12) or through opposing regulation of common targets (9,(13)(14)(15)(16).…”

mentioning

confidence: 99%

Regulation of MIR165/166 by class II and class III homeodomain leucine zipper proteins establishes leaf polarity

Merelo

Ram

Caggiano

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

101

View full text Add to dashboard Cite

A defining feature of plant leaves is their flattened shape. This shape depends on an antagonism between the genes that specify adaxial (top) and abaxial (bottom) tissue identity; however, the molecular nature of this antagonism remains poorly understood. Class III homeodomain leucine zipper (HD-ZIP) transcription factors are key mediators in the regulation of adaxial-abaxial patterning. Their expression is restricted adaxially during early development by the abaxially expressed microRNA (MIR)165/166, yet the mechanism that restricts MIR165/166 expression to abaxial leaf tissues remains unknown. Here, we show that class III and class II HD-ZIP proteins act together to repress MIR165/166 via a conserved cis-element in their promoters. Organ morphology and tissue patterning in plants, therefore, depend on a bidirectional repressive circuit involving a set of miRNAs and its targets. T he morphogenesis of lateral organs in plants and animals is dependent on the specification of distinct cell types early in development. In particular, the correct patterning of adaxialabaxial tissues in plant organs such as leaves is critical for the generation of a lamina shape and the formation of a polar vascular system (1-4). Adaxial-abaxial cell-type patterning in turn depends on the restricted expression of several genes known to specify these cell types, including the class III homeodomain leucine zipper genes (HD-ZIPIIIs), KANADI genes, HD-ZIPIIs, and microRNA (MIR)165/166 (1, 2, 4-11). In general, genetic analyses have indicated that adaxial and abaxial factors act oppositely in organ patterning (1,2,4,(8)(9)(10)(11). Hence, loss-of-function mutations in genes promoting adaxial cell identity typically cause an abaxialized phenotype that correlates with the ectopic expression of abaxial genes, whereas loss-of-function mutations in abaxial genes produce an adaxialized phenotype that is accompanied by the expanded expression of adaxial genes. This antagonistic interaction between adaxial and abaxial factors may be mediated by mutually antagonistic regulation (12) or through opposing regulation of common targets (9, 13-16).A key set of transcription factors involved in plant organ polarity are the HD-ZIPIII proteins, such as REVOLUTA (REV), which specify adaxial cell fate (1, 2, 4, 17). The expression of these genes is restricted specifically to adaxial tissues via the action of two miRNA families, MIR165 and MIR166 (2, 7). In turn, the expression of these miRNAs is restricted to abaxial tissues and this restriction is essential for maintaining proper organ polarity (18).Here, we address the question of how MIR165/166 are regulated. We show that the HD-ZIPII proteins HAT3 and ATHB4 physically interact with HD-ZIPIII proteins and directly repress MIR165/166 expression via a conserved cis-element located in their promoters. This regulatory interaction largely accounts for HAT3 and ATHB4 function and reveals the molecular nature of a bidirectional repressive circuit essential to maintain balance between adaxial and abaxial tissue sp...

show abstract

Establishing a Framework for the Ad/Abaxial Regulatory Network of Arabidopsis: Ascertaining Targets of Class III HOMEODOMAIN LEUCINE ZIPPER and KANADI Regulation

Cited by 94 publications

References 77 publications

The Sussex signal: insights into leaf dorsiventrality

The Sussex signal: insights into leaf dorsiventrality

Regulatory modules controlling maize inflorescence architecture

Regulation of MIR165/166 by class II and class III homeodomain leucine zipper proteins establishes leaf polarity

Contact Info

Product

Resources

About