The PLETHORA Gene Regulatory Network Guides Growth and Cell Differentiation in Arabidopsis Roots.

Organ formation in animals and plants relies on precise control of cell state transitions to turn stem cell daughters into fully differentiated cells. In plants, cells cannot rearrange due to shared cell walls. Thus, differentiation progression and the accompanying cell expansion must be tightly coordinated across tissues.

Detecting histone modifications in plants.

Histone modifications play an essential role in chromatin-associated processes including gene regulation and epigenetic inheritance. It is therefore very important to quantitatively analyze histone modifications at both the single gene and whole genome level. Here, we describe a robust chromatin immunoprecipitation (ChIP) method for Arabidopsis, which could be adapted for other plant species.

Shoot apical meristem function in Arabidopsis requires the combined activities of three BEL1-like homeodomain proteins.

In plants, most of the above-ground body is formed post-embryonically by the continuous organogenic potential of the shoot apical meristem (SAM). Proper function of the SAM requires maintenance of a delicate balance between the depletion of stem cell daughters into developing primordia and proliferation of the central stem cell population. Here we show that initiation and maintenance of the Arabidopsis SAM, including that of floral meristems, requires the combinatorial action of three members of the BELL-family of TALE homeodomain proteins, ARABIDOPSIS THALIANA HOMEOBOX 1 (ATH1), PENNYWISE (PNY) and POUND-FOOLISH (PNF).

The Arabidopsis TALE homeobox gene ATH1 controls floral competency through positive regulation of FLC.

Floral induction is controlled by a plethora of genes acting in different pathways that either repress or promote floral transition at the shoot apical meristem (SAM). During vegetative development high levels of floral repressors maintain the Arabidopsis SAM as incompetent to respond to promoting factors. Among these repressors, FLOWERING LOCUS C (FLC) is the most prominent.

Members of the aquaporin family in the developing pea seed coat include representatives of the PIP, TIP, and NIP subfamilies.

Water and nutrients required by developing seeds are mainly supplied by the phloem and have to be released from a maternal parenchyma tissue before being utilized by the filial tissues of embryo and endosperm. To identify aquaporins that could be involved in this process four full-length cDNAs were cloned and sequenced from a cDNA library of developing seed coats of pea (Pisum sativum L.).