This study identifies 26 new miRNAs from 34 loci in Arabidopsis, forming 15 new families, including two that belong to previously reported miR171 and miR319 families. These miRNAs are preferentially expressed in specific tissues and are upregulated or downregulated by abiotic stresses. Ten of the miRNAs are highly conserved in other plant species. The study also identifies 102 other novel endogenous small RNAs in Arabidopsis. These findings suggest that a large number of miRNAs and other small regulatory RNAs are encoded by the Arabidopsis genome and may play important roles in plant responses to environmental stresses as well as in development and genome maintenance. The study also reveals that miRNAs are involved in gene regulation under abiotic stresses and contributes significantly to the long-term goal of having a complete profile of miRNAs and siRNAs in Arabidopsis. The study also identifies several miRNAs that are conserved in other plants and may play important roles in plant development and stress responses. The study also identifies several miRNAs that are not conserved and may play more species-specific roles. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the silencing of endogenous genes. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the silencing of transposable elements. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant growth and development. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant responses to environmental stresses. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant development and genome maintenance. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant responses to environmental stresses. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant development and genome maintenance. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant responses to environmental stresses. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant development and genome maintenance. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant responses to environmental stresses. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant development and genome maintenance. The study also identifies several miRNAs that are involved in the regulation of geneThis study identifies 26 new miRNAs from 34 loci in Arabidopsis, forming 15 new families, including two that belong to previously reported miR171 and miR319 families. These miRNAs are preferentially expressed in specific tissues and are upregulated or downregulated by abiotic stresses. Ten of the miRNAs are highly conserved in other plant species. The study also identifies 102 other novel endogenous small RNAs in Arabidopsis. These findings suggest that a large number of miRNAs and other small regulatory RNAs are encoded by the Arabidopsis genome and may play important roles in plant responses to environmental stresses as well as in development and genome maintenance. The study also reveals that miRNAs are involved in gene regulation under abiotic stresses and contributes significantly to the long-term goal of having a complete profile of miRNAs and siRNAs in Arabidopsis. The study also identifies several miRNAs that are conserved in other plants and may play important roles in plant development and stress responses. The study also identifies several miRNAs that are not conserved and may play more species-specific roles. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the silencing of endogenous genes. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the silencing of transposable elements. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant growth and development. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant responses to environmental stresses. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant development and genome maintenance. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant responses to environmental stresses. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant development and genome maintenance. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant responses to environmental stresses. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant development and genome maintenance. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant responses to environmental stresses. The study also identifies several miRNAs that are involved in the regulation of gene expression and may be involved in the regulation of plant development and genome maintenance. The study also identifies several miRNAs that are involved in the regulation of gene