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Land plants develop highly diversified shoot architectures, all of which are derived from the pluripotent stem cells in shoot apical meristems (SAMs). As sustainable resources for continuous organ formation in the aboveground tissues, SAMs play an important role in determining plant yield and biomass production. In this review, we summarize recent advances in understanding one group of key regulators – the HAIRY MERISTEM (HAM) family GRAS domain proteins – in shoot meristems. We highlight the functions of HAM family members in dictating shoot stem cell initiation and proliferation, the signaling cascade that shapes HAM expression domains in shoot meristems, and the conservation and diversification of HAM family members in land plants. We also discuss future directions that potentially lead to a more comprehensive view of the HAM gene family and stem cell homeostasis in land plants.
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The Shoot Apical Meristem: A Tree’s Best Bud
Every spring, something seemingly miraculous happens in the woods in certain parts of the world—thousands of leaves burst from buds on bare tree branches, transforming the landscape from the browns and grays of winter to the bright greens of spring and summer. Although this process is most obvious in regions with drastic seasonal changes, seed plants all over the world regularly produce and lose leaves as they grow. How does this happen? Where do these leaves come from? The cells that make up these leaves are produced by a tiny cluster of cells called the shoot apical meristem. The cells in the shoot apical meristem have the potential to develop into various kinds of cells. Through cell division, meristem cells eventually produce all the above-ground parts of a plant, including leaves. In this article, we explain how meristems function and highlight how these tiny clusters of cells impact our day-to-day lives. We will also provide suggestions for observing meristems at work.
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- Award ID(s):
- 1652380
- PAR ID:
- 10410520
- Date Published:
- Journal Name:
- Frontiers for Young Minds
- Volume:
- 11
- ISSN:
- 2296-6846
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3389/frym.2023.965617
