新植物学家：日本科学家解析植物感受重力的分子机制
Fig. 1 Gravity-sensing locations in the shoots and roots.
(a) Illustration showing the whole Arabidopsis shoots and roots, including the lateral organs.
(b) Schematic structure of the Arabidopsis inflorescent stem region, as indicated by the upper dashed box in (a).
(c) Layer structure of the Arabidopsis inflorescent stem, as indicated by the dashed box in (b). From the outer most layer (right to left): Ep, epidermis; Co, cortex; En, endodermis; and St, stele.
(d) Cellular features of endodermal cells. Amyloplasts sediment toward the bottom of the cell according to the gravity vector. The cell is occupied by a large central vacuole.
(e) Photograph showing a primary root tip of Arabidopsis as indicated by the lower dashed box in (a). Columella cells contain amyloplasts (stained purple).
(f) Cellular features of columella cells. Amyloplasts sediment toward the bottom of the cell according to the gravity vector. Nucleus is in the upper part of the cell. In (d, f): N, nucleus; V, vacuole; A, amyloplast; S, starch granule.
Fig. 2 Schematic presentation of two proposed gravity-sensing models in the statocytes. (a, b) Mechanotransduction model. The actin filaments link to the stretch-activated Ca2+ channel. In the steady state, amyloplasts do not trigger the channel by pressing actin filaments (a). Once the amyloplasts move in response to gravistimulation, they provide a mechanical tension on
the actin filaments to activate the channel (b). (c, d) Position sensor model. The proximity or contact sites between the amyloplasts and plasma membrane induces local auxinflowin the cell, as indicated by the arrows. The sum of these local flows determines the direction of gross auxin flux.
Fig. 6 Schematic illustration of LZY function in the nucleus and plasma membrane. According to a study on rice, nuclear-localised LAZY1 is functional, and its nuclear localisation is inhibited by plasma membrane localised OsBRXL4 (blunt-ended arrow). In the nucleus (dashed circle), maize ZmLA1 interacts with IAA17 and wheat TaDRO1 interacts with TPL (double-headed arrow). While the interactions and nuclear localisation were reported, involvement of ZmLA1 in transcriptional regulation is open question (dashed blunt-ended arrow). In the plasma membrane, Arabidopsis LZY3 interacts with RLD1 on the bottom side of the cell. Some evidence suggests that the LZY–RLD complex interacts with GNOM and PID (double-headed arrows).
原文信息：Gravity sensing and responses in thecoordination of the shoot gravitropic setpointangle
