Regulation, Gene expression and Pattern of Growths Flashcards
affect the size, shape and structure of plants
• “genetic factors”
Gene/Protein Nomenclature Guidelines
In general, symbols for genes are ___, whereas symbols for proteins are ____
italicized
not italicized (e.g., IGF1).
All principal elements of the plant body are established by the ___ of embryogenesis, approximately four days after fertilization.
heart stage
___ transport of the hormone ___
is initiated at the early ___
and plays a key role in defining the main axis of
the embryo as well as promoting the
formation of the central vasculature.
Apical-to-basal
auxin
globular stage
In the absence of an auxin signal, ____ are
sequestered and inactivated by proteins of the
Aux/IAA family. Upon auxin signaling, Aux/IAAs
are rapidly degraded by the proteasome
The ability of a given cell to respond to auxin and
the nature of this response largely depend on
the repertoire of ARF and Aux/IAA genes it
expresses, suggesting that auxin may primarily
function as a _____
ARFs: Auxin Response Factor
modulating or permissive signal.
Steps in the auxin response pathway
- Auxin acts as a molecular glue bringing together Aux/IAAs and F-box proteins of the TIR1/AFB family.
- These F-box proteins are part of an SCF-type E3 ubiquitin protein ligase complex that transfers activated ubiquitin (Ub) from an E1/E2 enzyme system.
- Polyubiquitination of the Aux/IAAs results in their degradation.
- This releases repression at ARE-containing promoters.
___ always mark the positions of organ initiation
and, later, of the tips of developing organ primordia
Auxin maxima
PIN-FORMED (PIN)
Auxin Efflux Carrier
___proteins faithfully
predicts the flux of auxin, and ___ mutants
are impaired in auxin transport.
PIN , pin
which postulates that auxin acts to polarize
its own transport, this canalization is an
important part of the mechanism that
underlies coordinated tissue
polarization.
Canalization hypothesis
The ___, an influential model of ____(Sachs 1991), states that auxin flux is under ____: Cells will become polarized by ___ and increase their transport capacity to enhance auxin flux. Following this conceptually simple rule, preferred transport conduits can be selected in a field of cells and, once established, become stable. Cells located within these canals will differentiate into ___.
canalization hypothesis
vascu-larization
positive feedback control
auxin
vasculature
___ constructs, comprising a synthetic auxin-
responsive promoter driving the expression of a
reporter gene,
are widely used to visualize or measure transcriptional responses to auxin and to determine the position of what have been called ____
DR5: Reported Gene
auxin perception maxima
____ family Transcriptional factor and control involved in cell division, expansion
and show a dynamic expression in specific domains that
reveals the emergence of new cell fates with virtually every round of cell divisions in the pre-globular embryo WUS expressing cells regulate the stem cell population of the SAM.
WUSCHEL (WUS) family and WOX family
is required for pattern formation along the main body axis of the embryo in the flowering plant Arabidopsis thaliana.
Mutations in this gene alter the asymmetric division of the zygote and interfere with the formation of distinct apical-basal regions in the developing embryo!!!!!!
GNOM gene
what gene is involved with this? 
- the formation of distinct apical-basal regions in the
developing embryo.
- encodes an ARF guanine-nucleotide exchange
factor (ARF-GEF) that regulates the formation of
vesicles in membrane trafficking - involved in the endosomal recycling of
the auxin-efflux carrier PIN1 to the basal plasma membrane in provascular cells, which in turn is required for the accumulation of the plant hormone auxin at the future root pole through polar auxin transport.
GNOM gene
