TY  - JOUR
A1  - Vi, Son Lang
A1  - Trost, Gerda
A1  - Lange, Peggy
A1  - Czesnick, Hjördis
A1  - Rao, Nishta
A1  - Lieber, Diana
A1  - Laux, Thomas
A1  - Gray, William M.
A1  - Manley, James L.
A1  - Groth, Detlef
A1  - Kappel, Christian
A1  - Lenhard, Michael
T1  - Target specificity among canonical nuclear poly(A) polymerases in plants
 modulates organ growth and pathogen response
JF  - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF
 AMERICA
N2  - Polyadenylation of pre-mRNAs is critical for efficient nuclear export, stability, and translation of the mature mRNAs, and thus for gene expression. The bulk of pre-mRNAs are processed by canonical nuclear poly(A) polymerase (PAPS). Both vertebrate and higher-plant genomes encode more than one isoform of this enzyme, and these are coexpressed in different tissues. However, in neither case is it known whether the isoforms fulfill different functions or polyadenylate distinct subsets of pre-mRNAs. Here we show that the three canonical nuclear PAPS isoforms in Arabidopsis are functionally specialized owing to their evolutionarily divergent C-terminal domains. A strong loss-of-function mutation in PAPS1 causes a male gametophytic defect, whereas a weak allele leads to reduced leaf growth that results in part from a constitutive pathogen response. By contrast, plants lacking both PAPS2 and PAPS4 function are viable with wild-type leaf growth. Polyadenylation of SMALL AUXIN UP RNA (SAUR) mRNAs depends specifically on PAPS1 function. The resulting reduction in SAUR activity in paps1 mutants contributes to their reduced leaf growth, providing a causal link between polyadenylation of specific pre-mRNAs by a particular PAPS isoform and plant growth. This suggests the existence of an additional layer of regulation in plant and possibly vertebrate gene expression, whereby the relative activities of canonical nuclear PAPS isoforms control de novo synthesized poly(A) tail length and hence expression of specific subsets of mRNAs.
Y1  - 2013
U6  - https://doi.org/10.1073/pnas.1303967110
SN  - 0027-8424
VL  - 110
IS  - 34
SP  - 13994
EP  - 13999
PB  - NATL ACAD SCIENCES
CY  - WASHINGTON
ER  - 
TY  - JOUR
A1  - Tsukaya, Hirokazu
A1  - Byrne, Mary E.
A1  - Horiguchi, Gorou
A1  - Sugiyama, Munetaka
A1  - Van Lijsebettens, Mieke
A1  - Lenhard, Michael
T1  - How do 'housekeeping' genes control organogenesis?-unexpected new findings on the role of housekeeping genes in cell and organ differentiation
JF  - Journal of plant research
N2  - In recent years, an increasing number of mutations in what would appear to be 'housekeeping genes' have been identified as having unexpectedly specific defects in multicellular organogenesis. This is also the case for organogenesis in seed plants. Although it is not surprising that loss-of-function mutations in 'housekeeping' genes result in lethality or growth retardation, it is surprising when (1) the mutant phenotype results from the loss of function of a 'housekeeping' gene and (2) the mutant phenotype is specific. In this review, by defining housekeeping genes as those encoding proteins that work in basic metabolic and cellular functions, we discuss unexpected links between housekeeping genes and specific developmental processes. In a surprising number of cases housekeeping genes coding for enzymes or proteins with functions in basic cellular processes such as transcription, post-transcriptional modification, and translation affect plant development.
KW  - Development
KW  - Housekeeping genes
KW  - Post-transcriptional modification
KW  - RNAPII
KW  - Pre-mRNA splicing
KW  - Ribosome
KW  - 3 '-end processing
KW  - Transcription
KW  - Translation
Y1  - 2013
U6  - https://doi.org/10.1007/s10265-012-0518-2
SN  - 0918-9440
VL  - 126
IS  - 1
SP  - 3
EP  - 15
PB  - Springer
CY  - Tokyo
ER  - 
TY  - JOUR
A1  - Kierzkowski, Daniel
A1  - Lenhard, Michael
A1  - Smith, Richard
A1  - Kuhlemeier, Cris
T1  - Interaction between meristem tissue layers controls phyllotaxis
JF  - Developmental cell
N2  - Phyllotaxis and vein formation are among the most conspicuous patterning processes in plants. The expression and polarization of the auxin efflux carrier PIN1 is the earliest marker for both processes, with mathematical models indicating that PIN1 can respond to auxin gradients and/or auxin flux. Here, we use cell-layer-specific PIN1 knockouts and partial complementation of auxin transport mutants to examine the interaction between phyllotactic patterning, which occurs primarily in the L1 surface layer of the meristem, and midvein specification in the inner tissues. We show that PIN1 expression in the L1 is sufficient for correct organ positioning, as long as the L1-specific influx carriers are present. Thus, differentiation of inner tissues can proceed without PIN1 or any of the known polar transporters. On theoretical grounds, we suggest that canalization of auxin flux between an auxin source and an auxin sink may involve facilitated diffusion rather than polar transport.
Y1  - 2013
U6  - https://doi.org/10.1016/j.devcel.2013.08.017
SN  - 1534-5807
SN  - 1878-1551
VL  - 26
IS  - 6
SP  - 616
EP  - 628
PB  - Cell Press
CY  - Cambridge
ER  -