<div dir="ltr"><div dir="ltr"><div class="gmail_quote"><div dir="ltr" class="gmail_attr"><br></div><div dir="ltr"><div dir="ltr"><div class="gmail_quote"><div dir="ltr"><div class="gmail_quote"><br><div dir="ltr"><div class="gmail_quote"><div dir="ltr"><div style="text-align:center"><span style="font-family:georgia,serif;color:rgb(7,55,99);font-size:20pt;font-weight:700"> You are cordially </span><span style="font-family:georgia,serif;color:rgb(7,55,99);font-size:20pt;font-weight:700">invited</span><span style="font-family:georgia,serif;color:rgb(7,55,99);font-size:20pt;font-weight:700"> to attend</span></div><div><p style="text-align:center;direction:ltr;line-height:1.2;margin-top:4.2pt;margin-right:48.8pt;margin-bottom:0px"><span style="color:black"><span class="gmail_default"><font size="6" face="georgia, serif"> Jack Xu</font></span></span></p><p style="text-align:center;direction:ltr;line-height:1.2;margin-top:4.2pt;margin-right:48.8pt;margin-bottom:0px"><font color="#073763" face="georgia, serif"><b> UC Davis</b></font></p><p style="text-align:center;direction:ltr;line-height:1.2;margin-top:4.2pt;margin-right:48.8pt;margin-bottom:0px"><font color="#073763" face="georgia, serif"><b><br></b></font></p><font face="georgia, serif"><div style="text-align:center"><img src="cid:ii_m83opi8t0" alt="Picture.jpg" width="562" height="279"></div></font></div><div><div style="color:rgb(7,55,99);font-size:large;font-family:georgia,serif;text-align:center"><b><br></b></div><div style="color:rgb(7,55,99);font-size:large;text-align:center"><span style="color:rgb(34,34,34);text-align:start"><font face="georgia, serif"><b>Please join us for a CEPCEB and Community Coffee & Tea Social at 11:30am before the seminar</b></font></span></div><div style="color:rgb(7,55,99);font-size:large;font-family:georgia,serif;text-align:center"><span style="color:rgb(34,34,34);font-family:Arial,Helvetica,sans-serif;font-size:small;text-align:start"><br></span></div><div style="text-align:left"><p style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0.5pt;margin-right:48.8pt;margin-bottom:0px"><font size="4"><span style="color:black"><b>Date:</b> Friday, March <span class="gmail_default">21</span></span></font></p><p style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0.5pt;margin-right:48.8pt;margin-bottom:0px"><span style="color:black"><font size="4"><b>Time:</b> 12pm - 1:00 pm</font></span></p><p style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0.5pt;margin-right:48.8pt;margin-bottom:0px"><span style="color:black"><font size="4"><b>Location: </b>Genomics Auditorium 1102</font></span></p><p style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0.5pt;margin-right:48.8pt;margin-bottom:0px"><span style="font-size:large;color:black;text-align:left">OR</span></p><p style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0.5pt;margin-right:48.8pt;margin-bottom:0px"><a href="https://ucr.zoom.us/j/99288503164" style="font-size:12pt;text-align:left">https://ucr.zoom.us/j/99288503164</a></p><p style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0.5pt;margin-right:48.8pt;margin-bottom:0px"><span style="color:rgb(0,0,0);font-size:12pt">Meeting ID: 992 8850 3164 </span></p><p style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0.5pt;margin-right:48.8pt;margin-bottom:0px"><br></p><p style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0.5pt;margin-right:48.8pt;margin-bottom:0px"><br></p><div style="color:rgb(34,34,34);text-align:center"><b style="color:rgb(7,55,99);font-size:large"><font face="georgia, serif">Single-cell and Spatial Gene Expression Analysis Reveals Key Regulators of Stem Cell</font></b></div><p style="color:rgb(34,34,34);font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0.5pt;margin-right:48.8pt;margin-bottom:0px"><font color="#073763" style="font-family:Arial,Helvetica,sans-serif;text-align:start"></font></p><div style="color:rgb(7,55,99);font-size:large;font-family:georgia,serif;text-align:center"><b>Dynamics and Meristem Fate in Crop Inflorescence Development</b></div><div style="color:rgb(7,55,99);font-size:large;font-family:georgia,serif;text-align:center"><b><br></b></div><p style="color:rgb(34,34,34);font-family:georgia,serif;text-align:center;direction:ltr;line-height:1.2;margin-top:0px;margin-right:48.8pt;margin-bottom:0px"><span style="color:black"><b><font face="georgia, serif" size="4">Abstract:</font></b></span></p><p dir="ltr" style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:left;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;vertical-align:baseline"><font color="#000000">Stem cell regulation and meristem fate transitions are fundamental to plant shoot development and productivity, yet their genetic control remains difficult to decipher due to redundancy and pleiotropy. Leveraging high-resolution single-cell and spatial gene expression analysis combined with genome editing, we dissected key regulatory networks governing maize, wheat, and Arabidopsis inflorescence shoot development, leading to novel insights into stem cell maintenance, meristem identity, and crop yield-related traits.</font></span></p><p dir="ltr" style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:left;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;vertical-align:baseline"><font color="#000000"><br></font></span></p><p dir="ltr" style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:left;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;vertical-align:baseline"><font color="#000000">Through precise dissection of meristematic regions, we generated a stage-specific single-cell RNA sequencing (scRNA-seq) atlas of maize ear and tassel meristems, resolving dynamic transitions across the inflorescence meristem, spikelet pair meristem, spikelet meristem, floral meristem, and branch meristem stages (unpublished). This atlas uncovered previously uncharacterized transcription factors and signaling molecules defining meristem identity. Additionally, it enabled the large-scale recovery of shoot stem cells in maize and Arabidopsis, facilitating the efficient capture of thousands of CLAVATA3- and WUSCHEL-expressing cells (Xu et al., 2024, bioRxiv). Cross-species single-cell analysis followed by spatial gene expression validation identified conserved stem cell markers, including a SERPINE1 mRNA-binding protein family that regulates shoot meristem size. </font></span></p><p dir="ltr" style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:left;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;vertical-align:baseline"><font color="#000000"><br></font></span></p><p dir="ltr" style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:left;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;vertical-align:baseline"><font color="#000000">Building on this foundation, we conducted in-depth profiling of stem cell proliferation mutants, revealing regulatory shifts associated with meristem overgrowth. Further analysis uncovered WUSCHEL-targeted sugar kinase genes implicated in cytokinin homeostasis, with CRISPR genome editing providing functional insights into their roles in maintaining stem cell activity. </font></span></p><p dir="ltr" style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:left;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;vertical-align:baseline"><font color="#000000">Expanding beyond maize, we applied single cell and spatial gene expression analysis in wheat to map the spatial organization of gene expression in spikelet development (Xu et al., 2025, bioRxiv). Multiplex spatial profiling identified over 20 distinct gene expression domains governing meristem maintenance, organ differentiation, and vascular patterning. Comparative analyses of maize and wheat datasets highlighted both conserved and species-specific regulatory mechanisms shaping inflorescence architecture.</font></span></p><p dir="ltr" style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:left;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;vertical-align:baseline"><font color="#000000"> </font></span></p><p dir="ltr" style="color:rgb(34,34,34);font-size:small;font-family:georgia,serif;text-align:left;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;vertical-align:baseline"><font color="#000000">This work establishes a comprehensive single-cell and spatial gene expression framework for studying plant shoot meristem and stem cell dynamics. By integrating high-resolution transcriptomics with functional validation, we provide a transformative resource for understanding crop development and guiding future breeding strategies for improved agricultural productivity.</font></span></p></div><p style="direction:ltr;line-height:1.2;margin-top:4.2pt;margin-right:48.8pt;margin-bottom:0px"><font face="georgia, serif"></font></p><p style="text-align:center;line-height:1.2;margin-top:4.2pt;margin-bottom:0px;margin-left:48.8pt"><b style="text-align:left"><font face="verdana, sans-serif" color="#073763"> </font></b></p></div></div></div></div></div></div></div></div></div></div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><p class="MsoNormal"><font face="arial, sans-serif"></font></p></div></div></div>
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