scholarly journals Disentangling phylogenetic and functional components of shape variation among shoot apical meristems of a wide range of herbaceous angiosperms

2019 ◽  
Vol 107 (1) ◽  
pp. 20-30
Author(s):  
Renáta Schnablová ◽  
Jiří Neustupa ◽  
Kateřina Woodard ◽  
Jitka Klimešová ◽  
Tomáš Herben
Keyword(s):  
Shape Variation ◽  
Apical Meristems ◽  
Shoot Apical Meristems ◽  
Wide Range ◽  
Functional Components

The aba dynamics in leaves and shoot apical meristems (sam) of isogenic by E genes soybean lines under different photoperiod

2016 ◽  
Vol 48 (2) ◽  
pp. 167-177
Author(s):  
Yu.Yu. Yuhno ◽  
◽  
V.V. Zhmurko ◽  
Keyword(s):  
Apical Meristems ◽  
Shoot Apical Meristems

Differentiation of Multiple Shoot Apical Meristems in Mutant Rice with One Embryo Causing Multiple Plumuples

2012 ◽  
Vol 37 (12) ◽  
pp. 2251-2260
Author(s):  
Jing-Yu GUO ◽  
Zhi-Xiong CHEN ◽  
Bing-Yao YANG ◽  
Xin-Fen CHEN ◽  
Xiang-Dong LIU ◽  
...  
Keyword(s):  
Multiple Shoot ◽  
Apical Meristems ◽  
Shoot Apical Meristems

scholarly journals A developmentally descriptive method for quantifying shape in gastropod shells

2020 ◽  
Vol 17 (163) ◽  
pp. 20190721
Author(s):  
J. Larsson ◽  
A. M. Westram ◽  
S. Bengmark ◽  
T. Lundh ◽  
R. K. Butlin
Keyword(s):  
Empirical Studies ◽  
Three Dimensional ◽  
Shell Shape ◽  
Large Set ◽  
Littorina Saxatilis ◽  
Shape Variation ◽  
Gastropod Shell ◽  
Geometric Morphometric ◽  
Wide Range ◽  
Descriptive Method

The growth of snail shells can be described by simple mathematical rules. Variation in a few parameters can explain much of the diversity of shell shapes seen in nature. However, empirical studies of gastropod shell shape variation typically use geometric morphometric approaches, which do not capture this growth pattern. We have developed a way to infer a set of developmentally descriptive shape parameters based on three-dimensional logarithmic helicospiral growth and using landmarks from two-dimensional shell images as input. We demonstrate the utility of this approach, and compare it to the geometric morphometric approach, using a large set of Littorina saxatilis shells in which locally adapted populations differ in shape. Our method can be modified easily to make it applicable to a wide range of shell forms, which would allow for investigations of the similarities and differences between and within many different species of gastropods.

The effect of cadmium on shoot apical meristems of barley

2006 ◽  
Vol 37 (6) ◽  
pp. 371-374 ◽  
Author(s):  
N. M. Kaznina ◽  
G. F. Laidinen ◽  
A. F. Titov
Keyword(s):  
Apical Meristems ◽  
Shoot Apical Meristems

The PINHEAD/ZWILLE gene acts pleiotropically in Arabidopsis development and has overlapping functions with the ARGONAUTE1 gene

Development ◽  
1999 ◽  
Vol 126 (3) ◽  
pp. 469-481 ◽  
Author(s):  
K. Lynn ◽  
A. Fernandez ◽  
M. Aida ◽  
J. Sedbrook ◽  
M. Tasaka ◽  
...  
Keyword(s):  
Expression Patterns ◽  
Bilateral Symmetry ◽  
Floral Organ ◽  
Axillary Shoot ◽  
Apical Meristems ◽  
Shoot Apical Meristems ◽  
Positional Identity ◽  
Competence Factor ◽  
High Level

Several lines of evidence indicate that the adaxial leaf domain possesses a unique competence to form shoot apical meristems. Factors required for this competence are expected to cause a defect in shoot apical meristem formation when inactivated and to be expressed or active preferentially in the adaxial leaf domain. PINHEAD, a member of a family of proteins that includes the translation factor eIF2C, is required for reliable formation of primary and axillary shoot apical meristems. In addition to high-level expression in the vasculature, we find that low-level PINHEAD expression defines a novel domain of positional identity in the plant. This domain consists of adaxial leaf primordia and the meristem. These findings suggest that the PINHEAD gene product may be a component of a hypothetical meristem forming competence factor. We also describe defects in floral organ number and shape, as well as aberrant embryo and ovule development associated with pinhead mutants, thus elaborating on the role of PINHEAD in Arabidopsis development. In addition, we find that embryos doubly mutant for PINHEAD and ARGONAUTE1, a related, ubiquitously expressed family member, fail to progress to bilateral symmetry and do not accumulate the SHOOT MERISTEMLESS protein. Therefore PINHEAD and ARGONAUTE1 together act to allow wild-type growth and gene expression patterns during embryogenesis.

scholarly journals Stem Cell Maintenance in the Shoot Apical Meristems and during Axillary Meristem Development

CYTOLOGIA ◽  
2020 ◽  
Vol 85 (1) ◽  
pp. 3-8
Author(s):  
Hiro-Yuki Hirano ◽  
Wakana Tanaka
Keyword(s):  
Stem Cell ◽  
Axillary Meristem ◽  
Apical Meristems ◽  
Stem Cell Maintenance ◽  
Shoot Apical Meristems ◽  
Meristem Development ◽  
Cell Maintenance

scholarly journals Relative skull size as one of the factors limiting skull shape variation in passerines

2021 ◽  
Author(s):  
Oksana Shatkovska ◽  
Maria Ghazali
Keyword(s):  
Body Mass ◽  
Shape Variation ◽  
Absolute Size ◽  
Terrestrial Locomotion ◽  
Skull Shape ◽  
Skull Size ◽  
Dietary Preferences ◽  
Wide Range ◽  
Body Sizes ◽  
Biomechanical Constraints

Despite a considerable interest of researchers to the issue of variation in skull shapes of birds and factors influencing it, some drivers associated with the design features of an entire bird body, which are important for both successful terrestrial locomotion and flight, are overlooked. One of such factors, in our opinion, is relative skull size (skull length in relation to body mass), which can affect the position of the body's center of gravity. We tested effects of relative skull size, allometry (i.e. absolute skull size), and diet on variation in skull shape. The study was conducted on 50 songbird species with a wide range of body mass (8.3g to 570g) and dietary preferences (granivores, insectivores/granivores, insectivores, omnivores). Skull shape was analyzed using 2D geometric morphometrics. We revealed that similar patterns of skull shape occur among passerines with different body sizes and diets. The relative skull size predicted skull shape to a similar extent and with a similar pattern as the absolute size. In our opinion, the effect of the relative skull size on skull shape variation is likely due to biomechanical constraints related to flight.

scholarly journals Class I KNOX Is Related to Determinacy during the Leaf Development of the Fern Mickelia scandens (Dryopteridaceae)

2020 ◽  
Vol 21 (12) ◽  
pp. 4295 ◽  
Author(s):  
Rafael Cruz ◽  
Gladys F. A. Melo-de-Pinna ◽  
Alejandra Vasco ◽  
Jefferson Prado ◽  
Barbara A. Ambrose
Keyword(s):  
Leaf Development ◽  
Apical Meristem ◽  
Class I ◽  
Seed Plants ◽  
Histone H4 ◽  
Knox Genes ◽  
Apical Meristems ◽  
Cell Divisions ◽  
Shoot Apical Meristems

Unlike seed plants, ferns leaves are considered to be structures with delayed determinacy, with a leaf apical meristem similar to the shoot apical meristems. To better understand the meristematic organization during leaf development and determinacy control, we analyzed the cell divisions and expression of Class I KNOX genes in Mickelia scandens, a fern that produces larger leaves with more pinnae in its climbing form than in its terrestrial form. We performed anatomical, in situ hybridization, and qRT-PCR experiments with histone H4 (cell division marker) and Class I KNOX genes. We found that Class I KNOX genes are expressed in shoot apical meristems, leaf apical meristems, and pinnae primordia. During early development, cell divisions occur in the most distal regions of the analyzed structures, including pinnae, and are not restricted to apical cells. Fern leaves and pinnae bear apical meristems that may partially act as indeterminate shoots, supporting the hypothesis of homology between shoots and leaves. Class I KNOX expression is correlated with indeterminacy in the apex and leaf of ferns, suggesting a conserved function for these genes in euphyllophytes with compound leaves.

Sign in / Sign up

Export Citation Format

Share Document